[x86] Mitigate Microarchitectural Data Sampling (MDS) vulnerabilities

Together with a microcode update, this mitigates CVE-2018-12126,
CVE-2018-12127, CVE-2018-12130, and CVE-2019-11091.
This commit is contained in:
Ben Hutchings 2019-05-10 12:03:12 +01:00
parent 98cbc347d3
commit 1565dc00f4
32 changed files with 4186 additions and 0 deletions

33
debian/changelog vendored
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@ -1,6 +1,39 @@
linux (4.19.37-2) UNRELEASED; urgency=medium
* debian/bin: Fix Python static checker regressions (Closes: #928618)
* Clean up speculation mitigations:
- Documentation/l1tf: Fix small spelling typo
- x86/cpu: Sanitize FAM6_ATOM naming
- kvm: x86: Report STIBP on GET_SUPPORTED_CPUID
- x86/msr-index: Cleanup bit defines
- x86/speculation: Consolidate CPU whitelists
- Documentation: Move L1TF to separate directory
- cpu/speculation: Add 'mitigations=' cmdline option
- x86/speculation: Support 'mitigations=' cmdline option
- powerpc/speculation: Support 'mitigations=' cmdline option
- s390/speculation: Support 'mitigations=' cmdline option
- x86/speculation/mds: Add 'mitigations=' support for MDS
* [x86] Mitigate Microarchitectural Data Sampling (MDS) vulnerabilities
(CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, CVE-2019-11091):
- x86/speculation/mds: Add basic bug infrastructure for MDS
- x86/speculation/mds: Add BUG_MSBDS_ONLY
- x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
- x86/speculation/mds: Add mds_clear_cpu_buffers()
- x86/speculation/mds: Clear CPU buffers on exit to user
- x86/kvm/vmx: Add MDS protection when L1D Flush is not active
- x86/speculation/mds: Conditionally clear CPU buffers on idle entry
- x86/speculation/mds: Add mitigation control for MDS
- x86/speculation/mds: Add sysfs reporting for MDS
- x86/speculation/mds: Add mitigation mode VMWERV
- Documentation: Add MDS vulnerability documentation
- x86/speculation/mds: Add mds=full,nosmt cmdline option
- x86/speculation: Move arch_smt_update() call to after mitigation decisions
- x86/speculation/mds: Add SMT warning message
- x86/speculation/mds: Fix comment
- x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
- x86/mds: Add MDSUM variant to the MDS documentation
- Documentation: Correct the possible MDS sysfs values
- x86/speculation/mds: Fix documentation typo
-- Ben Hutchings <ben@decadent.org.uk> Tue, 07 May 2019 21:01:46 +0100

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@ -0,0 +1,40 @@
From 5a3e9a68c76f16a4d3d95b5703f8c0cbf1ce526c Mon Sep 17 00:00:00 2001
From: Salvatore Bonaccorso <carnil@debian.org>
Date: Wed, 15 Aug 2018 07:46:04 +0200
Subject: [PATCH 01/30] Documentation/l1tf: Fix small spelling typo
commit 60ca05c3b44566b70d64fbb8e87a6e0c67725468 upstream
Fix small typo (wiil -> will) in the "3.4. Nested virtual machines"
section.
Fixes: 5b76a3cff011 ("KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry")
Cc: linux-kernel@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-doc@vger.kernel.org
Cc: trivial@kernel.org
Signed-off-by: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/admin-guide/l1tf.rst | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/l1tf.rst b/Documentation/admin-guide/l1tf.rst
index 9f5924f81f89..9af977384168 100644
--- a/Documentation/admin-guide/l1tf.rst
+++ b/Documentation/admin-guide/l1tf.rst
@@ -556,7 +556,7 @@ carefully analyzed. For full protection the following methods are
the bare metal hypervisor, the nested hypervisor and the nested virtual
machine. VMENTER operations from the nested hypervisor into the nested
guest will always be processed by the bare metal hypervisor. If KVM is the
-bare metal hypervisor it wiil:
+bare metal hypervisor it will:
- Flush the L1D cache on every switch from the nested hypervisor to the
nested virtual machine, so that the nested hypervisor's secrets are not

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@ -0,0 +1,782 @@
From fae627376bb7cb519a54a1ac372623653a170317 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Tue, 7 Aug 2018 10:17:27 -0700
Subject: [PATCH 02/30] x86/cpu: Sanitize FAM6_ATOM naming
commit f2c4db1bd80720cd8cb2a5aa220d9bc9f374f04e upstream
Going primarily by:
https://en.wikipedia.org/wiki/List_of_Intel_Atom_microprocessors
with additional information gleaned from other related pages; notably:
- Bonnell shrink was called Saltwell
- Moorefield is the Merriefield refresh which makes it Airmont
The general naming scheme is: FAM6_ATOM_UARCH_SOCTYPE
for i in `git grep -l FAM6_ATOM` ; do
sed -i -e 's/ATOM_PINEVIEW/ATOM_BONNELL/g' \
-e 's/ATOM_LINCROFT/ATOM_BONNELL_MID/' \
-e 's/ATOM_PENWELL/ATOM_SALTWELL_MID/g' \
-e 's/ATOM_CLOVERVIEW/ATOM_SALTWELL_TABLET/g' \
-e 's/ATOM_CEDARVIEW/ATOM_SALTWELL/g' \
-e 's/ATOM_SILVERMONT1/ATOM_SILVERMONT/g' \
-e 's/ATOM_SILVERMONT2/ATOM_SILVERMONT_X/g' \
-e 's/ATOM_MERRIFIELD/ATOM_SILVERMONT_MID/g' \
-e 's/ATOM_MOOREFIELD/ATOM_AIRMONT_MID/g' \
-e 's/ATOM_DENVERTON/ATOM_GOLDMONT_X/g' \
-e 's/ATOM_GEMINI_LAKE/ATOM_GOLDMONT_PLUS/g' ${i}
done
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: dave.hansen@linux.intel.com
Cc: len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/events/intel/core.c | 20 ++++----
arch/x86/events/intel/cstate.c | 8 ++--
arch/x86/events/intel/rapl.c | 4 +-
arch/x86/events/msr.c | 8 ++--
arch/x86/include/asm/intel-family.h | 33 ++++++-------
arch/x86/kernel/cpu/common.c | 28 +++++------
arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c | 4 +-
arch/x86/kernel/tsc.c | 2 +-
arch/x86/kernel/tsc_msr.c | 10 ++--
arch/x86/platform/atom/punit_atom_debug.c | 4 +-
.../intel-mid/device_libs/platform_bt.c | 2 +-
drivers/acpi/acpi_lpss.c | 2 +-
drivers/acpi/x86/utils.c | 2 +-
drivers/cpufreq/intel_pstate.c | 4 +-
drivers/edac/pnd2_edac.c | 2 +-
drivers/idle/intel_idle.c | 18 ++++----
drivers/mmc/host/sdhci-acpi.c | 2 +-
drivers/pci/pci-mid.c | 4 +-
drivers/platform/x86/intel_int0002_vgpio.c | 2 +-
drivers/platform/x86/intel_mid_powerbtn.c | 4 +-
.../platform/x86/intel_telemetry_debugfs.c | 2 +-
drivers/platform/x86/intel_telemetry_pltdrv.c | 2 +-
drivers/powercap/intel_rapl.c | 10 ++--
drivers/thermal/intel_soc_dts_thermal.c | 2 +-
sound/soc/intel/boards/bytcr_rt5651.c | 2 +-
tools/power/x86/turbostat/turbostat.c | 46 +++++++++----------
26 files changed, 115 insertions(+), 112 deletions(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 3dd204d1dd19..a82c7b655d77 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4126,11 +4126,11 @@ __init int intel_pmu_init(void)
name = "nehalem";
break;
- case INTEL_FAM6_ATOM_PINEVIEW:
- case INTEL_FAM6_ATOM_LINCROFT:
- case INTEL_FAM6_ATOM_PENWELL:
- case INTEL_FAM6_ATOM_CLOVERVIEW:
- case INTEL_FAM6_ATOM_CEDARVIEW:
+ case INTEL_FAM6_ATOM_BONNELL:
+ case INTEL_FAM6_ATOM_BONNELL_MID:
+ case INTEL_FAM6_ATOM_SALTWELL:
+ case INTEL_FAM6_ATOM_SALTWELL_MID:
+ case INTEL_FAM6_ATOM_SALTWELL_TABLET:
memcpy(hw_cache_event_ids, atom_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
@@ -4143,9 +4143,11 @@ __init int intel_pmu_init(void)
name = "bonnell";
break;
- case INTEL_FAM6_ATOM_SILVERMONT1:
- case INTEL_FAM6_ATOM_SILVERMONT2:
+ case INTEL_FAM6_ATOM_SILVERMONT:
+ case INTEL_FAM6_ATOM_SILVERMONT_X:
+ case INTEL_FAM6_ATOM_SILVERMONT_MID:
case INTEL_FAM6_ATOM_AIRMONT:
+ case INTEL_FAM6_ATOM_AIRMONT_MID:
memcpy(hw_cache_event_ids, slm_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
memcpy(hw_cache_extra_regs, slm_hw_cache_extra_regs,
@@ -4164,7 +4166,7 @@ __init int intel_pmu_init(void)
break;
case INTEL_FAM6_ATOM_GOLDMONT:
- case INTEL_FAM6_ATOM_DENVERTON:
+ case INTEL_FAM6_ATOM_GOLDMONT_X:
memcpy(hw_cache_event_ids, glm_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
memcpy(hw_cache_extra_regs, glm_hw_cache_extra_regs,
@@ -4190,7 +4192,7 @@ __init int intel_pmu_init(void)
name = "goldmont";
break;
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
memcpy(hw_cache_event_ids, glp_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
memcpy(hw_cache_extra_regs, glp_hw_cache_extra_regs,
diff --git a/arch/x86/events/intel/cstate.c b/arch/x86/events/intel/cstate.c
index 6eb76106c469..56194c571299 100644
--- a/arch/x86/events/intel/cstate.c
+++ b/arch/x86/events/intel/cstate.c
@@ -559,8 +559,8 @@ static const struct x86_cpu_id intel_cstates_match[] __initconst = {
X86_CSTATES_MODEL(INTEL_FAM6_HASWELL_ULT, hswult_cstates),
- X86_CSTATES_MODEL(INTEL_FAM6_ATOM_SILVERMONT1, slm_cstates),
- X86_CSTATES_MODEL(INTEL_FAM6_ATOM_SILVERMONT2, slm_cstates),
+ X86_CSTATES_MODEL(INTEL_FAM6_ATOM_SILVERMONT, slm_cstates),
+ X86_CSTATES_MODEL(INTEL_FAM6_ATOM_SILVERMONT_X, slm_cstates),
X86_CSTATES_MODEL(INTEL_FAM6_ATOM_AIRMONT, slm_cstates),
X86_CSTATES_MODEL(INTEL_FAM6_BROADWELL_CORE, snb_cstates),
@@ -581,9 +581,9 @@ static const struct x86_cpu_id intel_cstates_match[] __initconst = {
X86_CSTATES_MODEL(INTEL_FAM6_XEON_PHI_KNM, knl_cstates),
X86_CSTATES_MODEL(INTEL_FAM6_ATOM_GOLDMONT, glm_cstates),
- X86_CSTATES_MODEL(INTEL_FAM6_ATOM_DENVERTON, glm_cstates),
+ X86_CSTATES_MODEL(INTEL_FAM6_ATOM_GOLDMONT_X, glm_cstates),
- X86_CSTATES_MODEL(INTEL_FAM6_ATOM_GEMINI_LAKE, glm_cstates),
+ X86_CSTATES_MODEL(INTEL_FAM6_ATOM_GOLDMONT_PLUS, glm_cstates),
{ },
};
MODULE_DEVICE_TABLE(x86cpu, intel_cstates_match);
diff --git a/arch/x86/events/intel/rapl.c b/arch/x86/events/intel/rapl.c
index 32f3e9423e99..91039ffed633 100644
--- a/arch/x86/events/intel/rapl.c
+++ b/arch/x86/events/intel/rapl.c
@@ -777,9 +777,9 @@ static const struct x86_cpu_id rapl_cpu_match[] __initconst = {
X86_RAPL_MODEL_MATCH(INTEL_FAM6_CANNONLAKE_MOBILE, skl_rapl_init),
X86_RAPL_MODEL_MATCH(INTEL_FAM6_ATOM_GOLDMONT, hsw_rapl_init),
- X86_RAPL_MODEL_MATCH(INTEL_FAM6_ATOM_DENVERTON, hsw_rapl_init),
+ X86_RAPL_MODEL_MATCH(INTEL_FAM6_ATOM_GOLDMONT_X, hsw_rapl_init),
- X86_RAPL_MODEL_MATCH(INTEL_FAM6_ATOM_GEMINI_LAKE, hsw_rapl_init),
+ X86_RAPL_MODEL_MATCH(INTEL_FAM6_ATOM_GOLDMONT_PLUS, hsw_rapl_init),
{},
};
diff --git a/arch/x86/events/msr.c b/arch/x86/events/msr.c
index b4771a6ddbc1..1b9f85abf9bc 100644
--- a/arch/x86/events/msr.c
+++ b/arch/x86/events/msr.c
@@ -69,14 +69,14 @@ static bool test_intel(int idx)
case INTEL_FAM6_BROADWELL_GT3E:
case INTEL_FAM6_BROADWELL_X:
- case INTEL_FAM6_ATOM_SILVERMONT1:
- case INTEL_FAM6_ATOM_SILVERMONT2:
+ case INTEL_FAM6_ATOM_SILVERMONT:
+ case INTEL_FAM6_ATOM_SILVERMONT_X:
case INTEL_FAM6_ATOM_AIRMONT:
case INTEL_FAM6_ATOM_GOLDMONT:
- case INTEL_FAM6_ATOM_DENVERTON:
+ case INTEL_FAM6_ATOM_GOLDMONT_X:
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
case INTEL_FAM6_XEON_PHI_KNL:
case INTEL_FAM6_XEON_PHI_KNM:
diff --git a/arch/x86/include/asm/intel-family.h b/arch/x86/include/asm/intel-family.h
index 0ad25cc895ae..058b1a1994c4 100644
--- a/arch/x86/include/asm/intel-family.h
+++ b/arch/x86/include/asm/intel-family.h
@@ -8,9 +8,6 @@
* The "_X" parts are generally the EP and EX Xeons, or the
* "Extreme" ones, like Broadwell-E.
*
- * Things ending in "2" are usually because we have no better
- * name for them. There's no processor called "SILVERMONT2".
- *
* While adding a new CPUID for a new microarchitecture, add a new
* group to keep logically sorted out in chronological order. Within
* that group keep the CPUID for the variants sorted by model number.
@@ -59,19 +56,23 @@
/* "Small Core" Processors (Atom) */
-#define INTEL_FAM6_ATOM_PINEVIEW 0x1C
-#define INTEL_FAM6_ATOM_LINCROFT 0x26
-#define INTEL_FAM6_ATOM_PENWELL 0x27
-#define INTEL_FAM6_ATOM_CLOVERVIEW 0x35
-#define INTEL_FAM6_ATOM_CEDARVIEW 0x36
-#define INTEL_FAM6_ATOM_SILVERMONT1 0x37 /* BayTrail/BYT / Valleyview */
-#define INTEL_FAM6_ATOM_SILVERMONT2 0x4D /* Avaton/Rangely */
-#define INTEL_FAM6_ATOM_AIRMONT 0x4C /* CherryTrail / Braswell */
-#define INTEL_FAM6_ATOM_MERRIFIELD 0x4A /* Tangier */
-#define INTEL_FAM6_ATOM_MOOREFIELD 0x5A /* Anniedale */
-#define INTEL_FAM6_ATOM_GOLDMONT 0x5C
-#define INTEL_FAM6_ATOM_DENVERTON 0x5F /* Goldmont Microserver */
-#define INTEL_FAM6_ATOM_GEMINI_LAKE 0x7A
+#define INTEL_FAM6_ATOM_BONNELL 0x1C /* Diamondville, Pineview */
+#define INTEL_FAM6_ATOM_BONNELL_MID 0x26 /* Silverthorne, Lincroft */
+
+#define INTEL_FAM6_ATOM_SALTWELL 0x36 /* Cedarview */
+#define INTEL_FAM6_ATOM_SALTWELL_MID 0x27 /* Penwell */
+#define INTEL_FAM6_ATOM_SALTWELL_TABLET 0x35 /* Cloverview */
+
+#define INTEL_FAM6_ATOM_SILVERMONT 0x37 /* Bay Trail, Valleyview */
+#define INTEL_FAM6_ATOM_SILVERMONT_X 0x4D /* Avaton, Rangely */
+#define INTEL_FAM6_ATOM_SILVERMONT_MID 0x4A /* Merriefield */
+
+#define INTEL_FAM6_ATOM_AIRMONT 0x4C /* Cherry Trail, Braswell */
+#define INTEL_FAM6_ATOM_AIRMONT_MID 0x5A /* Moorefield */
+
+#define INTEL_FAM6_ATOM_GOLDMONT 0x5C /* Apollo Lake */
+#define INTEL_FAM6_ATOM_GOLDMONT_X 0x5F /* Denverton */
+#define INTEL_FAM6_ATOM_GOLDMONT_PLUS 0x7A /* Gemini Lake */
/* Xeon Phi */
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 44c4ef3d989b..10e5ccfa9278 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -949,11 +949,11 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
}
static const __initconst struct x86_cpu_id cpu_no_speculation[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CEDARVIEW, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CLOVERVIEW, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_LINCROFT, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PENWELL, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PINEVIEW, X86_FEATURE_ANY },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL, X86_FEATURE_ANY },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL_TABLET, X86_FEATURE_ANY },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_BONNELL_MID, X86_FEATURE_ANY },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL_MID, X86_FEATURE_ANY },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_BONNELL, X86_FEATURE_ANY },
{ X86_VENDOR_CENTAUR, 5 },
{ X86_VENDOR_INTEL, 5 },
{ X86_VENDOR_NSC, 5 },
@@ -968,10 +968,10 @@ static const __initconst struct x86_cpu_id cpu_no_meltdown[] = {
/* Only list CPUs which speculate but are non susceptible to SSB */
static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_MERRIFIELD },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_X },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_MID },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
@@ -984,14 +984,14 @@ static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
static const __initconst struct x86_cpu_id cpu_no_l1tf[] = {
/* in addition to cpu_no_speculation */
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_X },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_MERRIFIELD },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_MOOREFIELD },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_MID },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT_MID },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_DENVERTON },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GEMINI_LAKE },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT_X },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT_PLUS },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
{}
diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
index f8c260d522ca..912d53939f4f 100644
--- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
+++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c
@@ -91,7 +91,7 @@ static u64 get_prefetch_disable_bits(void)
*/
return 0xF;
case INTEL_FAM6_ATOM_GOLDMONT:
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
/*
* SDM defines bits of MSR_MISC_FEATURE_CONTROL register
* as:
@@ -995,7 +995,7 @@ static int measure_cycles_perf_fn(void *_plr)
switch (boot_cpu_data.x86_model) {
case INTEL_FAM6_ATOM_GOLDMONT:
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
l2_hit_bits = (0x52ULL << 16) | (0x2 << 8) | 0xd1;
l2_miss_bits = (0x52ULL << 16) | (0x10 << 8) | 0xd1;
break;
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 6d5dc5dabfd7..03b7529333a6 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -636,7 +636,7 @@ unsigned long native_calibrate_tsc(void)
case INTEL_FAM6_KABYLAKE_DESKTOP:
crystal_khz = 24000; /* 24.0 MHz */
break;
- case INTEL_FAM6_ATOM_DENVERTON:
+ case INTEL_FAM6_ATOM_GOLDMONT_X:
crystal_khz = 25000; /* 25.0 MHz */
break;
case INTEL_FAM6_ATOM_GOLDMONT:
diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c
index 27ef714d886c..3d0e9aeea7c8 100644
--- a/arch/x86/kernel/tsc_msr.c
+++ b/arch/x86/kernel/tsc_msr.c
@@ -59,12 +59,12 @@ static const struct freq_desc freq_desc_ann = {
};
static const struct x86_cpu_id tsc_msr_cpu_ids[] = {
- INTEL_CPU_FAM6(ATOM_PENWELL, freq_desc_pnw),
- INTEL_CPU_FAM6(ATOM_CLOVERVIEW, freq_desc_clv),
- INTEL_CPU_FAM6(ATOM_SILVERMONT1, freq_desc_byt),
+ INTEL_CPU_FAM6(ATOM_SALTWELL_MID, freq_desc_pnw),
+ INTEL_CPU_FAM6(ATOM_SALTWELL_TABLET, freq_desc_clv),
+ INTEL_CPU_FAM6(ATOM_SILVERMONT, freq_desc_byt),
+ INTEL_CPU_FAM6(ATOM_SILVERMONT_MID, freq_desc_tng),
INTEL_CPU_FAM6(ATOM_AIRMONT, freq_desc_cht),
- INTEL_CPU_FAM6(ATOM_MERRIFIELD, freq_desc_tng),
- INTEL_CPU_FAM6(ATOM_MOOREFIELD, freq_desc_ann),
+ INTEL_CPU_FAM6(ATOM_AIRMONT_MID, freq_desc_ann),
{}
};
diff --git a/arch/x86/platform/atom/punit_atom_debug.c b/arch/x86/platform/atom/punit_atom_debug.c
index 034813d4ab1e..41dae0f0d898 100644
--- a/arch/x86/platform/atom/punit_atom_debug.c
+++ b/arch/x86/platform/atom/punit_atom_debug.c
@@ -143,8 +143,8 @@ static void punit_dbgfs_unregister(void)
(kernel_ulong_t)&drv_data }
static const struct x86_cpu_id intel_punit_cpu_ids[] = {
- ICPU(INTEL_FAM6_ATOM_SILVERMONT1, punit_device_byt),
- ICPU(INTEL_FAM6_ATOM_MERRIFIELD, punit_device_tng),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT, punit_device_byt),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID, punit_device_tng),
ICPU(INTEL_FAM6_ATOM_AIRMONT, punit_device_cht),
{}
};
diff --git a/arch/x86/platform/intel-mid/device_libs/platform_bt.c b/arch/x86/platform/intel-mid/device_libs/platform_bt.c
index 5a0483e7bf66..31dce781364c 100644
--- a/arch/x86/platform/intel-mid/device_libs/platform_bt.c
+++ b/arch/x86/platform/intel-mid/device_libs/platform_bt.c
@@ -68,7 +68,7 @@ static struct bt_sfi_data tng_bt_sfi_data __initdata = {
{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (kernel_ulong_t)&ddata }
static const struct x86_cpu_id bt_sfi_cpu_ids[] = {
- ICPU(INTEL_FAM6_ATOM_MERRIFIELD, tng_bt_sfi_data),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID, tng_bt_sfi_data),
{}
};
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 969bf8d515c0..c651e206d796 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -292,7 +292,7 @@ static const struct lpss_device_desc bsw_spi_dev_desc = {
#define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
static const struct x86_cpu_id lpss_cpu_ids[] = {
- ICPU(INTEL_FAM6_ATOM_SILVERMONT1), /* Valleyview, Bay Trail */
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT), /* Valleyview, Bay Trail */
ICPU(INTEL_FAM6_ATOM_AIRMONT), /* Braswell, Cherry Trail */
{}
};
diff --git a/drivers/acpi/x86/utils.c b/drivers/acpi/x86/utils.c
index 06c31ec3cc70..9a8e286dd86f 100644
--- a/drivers/acpi/x86/utils.c
+++ b/drivers/acpi/x86/utils.c
@@ -54,7 +54,7 @@ static const struct always_present_id always_present_ids[] = {
* Bay / Cherry Trail PWM directly poked by GPU driver in win10,
* but Linux uses a separate PWM driver, harmless if not used.
*/
- ENTRY("80860F09", "1", ICPU(INTEL_FAM6_ATOM_SILVERMONT1), {}),
+ ENTRY("80860F09", "1", ICPU(INTEL_FAM6_ATOM_SILVERMONT), {}),
ENTRY("80862288", "1", ICPU(INTEL_FAM6_ATOM_AIRMONT), {}),
/*
* The INT0002 device is necessary to clear wakeup interrupt sources
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index a005711f909e..29f25d5d65e0 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1779,7 +1779,7 @@ static const struct pstate_funcs knl_funcs = {
static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
ICPU(INTEL_FAM6_SANDYBRIDGE, core_funcs),
ICPU(INTEL_FAM6_SANDYBRIDGE_X, core_funcs),
- ICPU(INTEL_FAM6_ATOM_SILVERMONT1, silvermont_funcs),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT, silvermont_funcs),
ICPU(INTEL_FAM6_IVYBRIDGE, core_funcs),
ICPU(INTEL_FAM6_HASWELL_CORE, core_funcs),
ICPU(INTEL_FAM6_BROADWELL_CORE, core_funcs),
@@ -1796,7 +1796,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
ICPU(INTEL_FAM6_XEON_PHI_KNL, knl_funcs),
ICPU(INTEL_FAM6_XEON_PHI_KNM, knl_funcs),
ICPU(INTEL_FAM6_ATOM_GOLDMONT, core_funcs),
- ICPU(INTEL_FAM6_ATOM_GEMINI_LAKE, core_funcs),
+ ICPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS, core_funcs),
ICPU(INTEL_FAM6_SKYLAKE_X, core_funcs),
{}
};
diff --git a/drivers/edac/pnd2_edac.c b/drivers/edac/pnd2_edac.c
index df28b65358d2..903a4f1fadcc 100644
--- a/drivers/edac/pnd2_edac.c
+++ b/drivers/edac/pnd2_edac.c
@@ -1541,7 +1541,7 @@ static struct dunit_ops dnv_ops = {
static const struct x86_cpu_id pnd2_cpuids[] = {
{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT, 0, (kernel_ulong_t)&apl_ops },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_DENVERTON, 0, (kernel_ulong_t)&dnv_ops },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT_X, 0, (kernel_ulong_t)&dnv_ops },
{ }
};
MODULE_DEVICE_TABLE(x86cpu, pnd2_cpuids);
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index b2ccce5fb071..c4bb67ed8da3 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1076,14 +1076,14 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_WESTMERE, idle_cpu_nehalem),
ICPU(INTEL_FAM6_WESTMERE_EP, idle_cpu_nehalem),
ICPU(INTEL_FAM6_NEHALEM_EX, idle_cpu_nehalem),
- ICPU(INTEL_FAM6_ATOM_PINEVIEW, idle_cpu_atom),
- ICPU(INTEL_FAM6_ATOM_LINCROFT, idle_cpu_lincroft),
+ ICPU(INTEL_FAM6_ATOM_BONNELL, idle_cpu_atom),
+ ICPU(INTEL_FAM6_ATOM_BONNELL_MID, idle_cpu_lincroft),
ICPU(INTEL_FAM6_WESTMERE_EX, idle_cpu_nehalem),
ICPU(INTEL_FAM6_SANDYBRIDGE, idle_cpu_snb),
ICPU(INTEL_FAM6_SANDYBRIDGE_X, idle_cpu_snb),
- ICPU(INTEL_FAM6_ATOM_CEDARVIEW, idle_cpu_atom),
- ICPU(INTEL_FAM6_ATOM_SILVERMONT1, idle_cpu_byt),
- ICPU(INTEL_FAM6_ATOM_MERRIFIELD, idle_cpu_tangier),
+ ICPU(INTEL_FAM6_ATOM_SALTWELL, idle_cpu_atom),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT, idle_cpu_byt),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID, idle_cpu_tangier),
ICPU(INTEL_FAM6_ATOM_AIRMONT, idle_cpu_cht),
ICPU(INTEL_FAM6_IVYBRIDGE, idle_cpu_ivb),
ICPU(INTEL_FAM6_IVYBRIDGE_X, idle_cpu_ivt),
@@ -1091,7 +1091,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_HASWELL_X, idle_cpu_hsw),
ICPU(INTEL_FAM6_HASWELL_ULT, idle_cpu_hsw),
ICPU(INTEL_FAM6_HASWELL_GT3E, idle_cpu_hsw),
- ICPU(INTEL_FAM6_ATOM_SILVERMONT2, idle_cpu_avn),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_X, idle_cpu_avn),
ICPU(INTEL_FAM6_BROADWELL_CORE, idle_cpu_bdw),
ICPU(INTEL_FAM6_BROADWELL_GT3E, idle_cpu_bdw),
ICPU(INTEL_FAM6_BROADWELL_X, idle_cpu_bdw),
@@ -1104,8 +1104,8 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_XEON_PHI_KNL, idle_cpu_knl),
ICPU(INTEL_FAM6_XEON_PHI_KNM, idle_cpu_knl),
ICPU(INTEL_FAM6_ATOM_GOLDMONT, idle_cpu_bxt),
- ICPU(INTEL_FAM6_ATOM_GEMINI_LAKE, idle_cpu_bxt),
- ICPU(INTEL_FAM6_ATOM_DENVERTON, idle_cpu_dnv),
+ ICPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS, idle_cpu_bxt),
+ ICPU(INTEL_FAM6_ATOM_GOLDMONT_X, idle_cpu_dnv),
{}
};
@@ -1322,7 +1322,7 @@ static void intel_idle_state_table_update(void)
ivt_idle_state_table_update();
break;
case INTEL_FAM6_ATOM_GOLDMONT:
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
bxt_idle_state_table_update();
break;
case INTEL_FAM6_SKYLAKE_DESKTOP:
diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
index c61109f7b793..57c1ec322e42 100644
--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -247,7 +247,7 @@ static const struct sdhci_acpi_chip sdhci_acpi_chip_int = {
static bool sdhci_acpi_byt(void)
{
static const struct x86_cpu_id byt[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT },
{}
};
diff --git a/drivers/pci/pci-mid.c b/drivers/pci/pci-mid.c
index 314e135014dc..30fbe2ea6eab 100644
--- a/drivers/pci/pci-mid.c
+++ b/drivers/pci/pci-mid.c
@@ -62,8 +62,8 @@ static const struct pci_platform_pm_ops mid_pci_platform_pm = {
* arch/x86/platform/intel-mid/pwr.c.
*/
static const struct x86_cpu_id lpss_cpu_ids[] = {
- ICPU(INTEL_FAM6_ATOM_PENWELL),
- ICPU(INTEL_FAM6_ATOM_MERRIFIELD),
+ ICPU(INTEL_FAM6_ATOM_SALTWELL_MID),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID),
{}
};
diff --git a/drivers/platform/x86/intel_int0002_vgpio.c b/drivers/platform/x86/intel_int0002_vgpio.c
index a473dc51b18d..e89ad4964dc1 100644
--- a/drivers/platform/x86/intel_int0002_vgpio.c
+++ b/drivers/platform/x86/intel_int0002_vgpio.c
@@ -60,7 +60,7 @@ static const struct x86_cpu_id int0002_cpu_ids[] = {
/*
* Limit ourselves to Cherry Trail for now, until testing shows we
* need to handle the INT0002 device on Baytrail too.
- * ICPU(INTEL_FAM6_ATOM_SILVERMONT1), * Valleyview, Bay Trail *
+ * ICPU(INTEL_FAM6_ATOM_SILVERMONT), * Valleyview, Bay Trail *
*/
ICPU(INTEL_FAM6_ATOM_AIRMONT), /* Braswell, Cherry Trail */
{}
diff --git a/drivers/platform/x86/intel_mid_powerbtn.c b/drivers/platform/x86/intel_mid_powerbtn.c
index d79fbf924b13..5ad44204a9c3 100644
--- a/drivers/platform/x86/intel_mid_powerbtn.c
+++ b/drivers/platform/x86/intel_mid_powerbtn.c
@@ -125,8 +125,8 @@ static const struct mid_pb_ddata mrfld_ddata = {
{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (kernel_ulong_t)&ddata }
static const struct x86_cpu_id mid_pb_cpu_ids[] = {
- ICPU(INTEL_FAM6_ATOM_PENWELL, mfld_ddata),
- ICPU(INTEL_FAM6_ATOM_MERRIFIELD, mrfld_ddata),
+ ICPU(INTEL_FAM6_ATOM_SALTWELL_MID, mfld_ddata),
+ ICPU(INTEL_FAM6_ATOM_SILVERMONT_MID, mrfld_ddata),
{}
};
diff --git a/drivers/platform/x86/intel_telemetry_debugfs.c b/drivers/platform/x86/intel_telemetry_debugfs.c
index 1423fa8710fd..b998d7da97fb 100644
--- a/drivers/platform/x86/intel_telemetry_debugfs.c
+++ b/drivers/platform/x86/intel_telemetry_debugfs.c
@@ -320,7 +320,7 @@ static struct telemetry_debugfs_conf telem_apl_debugfs_conf = {
static const struct x86_cpu_id telemetry_debugfs_cpu_ids[] = {
TELEM_DEBUGFS_CPU(INTEL_FAM6_ATOM_GOLDMONT, telem_apl_debugfs_conf),
- TELEM_DEBUGFS_CPU(INTEL_FAM6_ATOM_GEMINI_LAKE, telem_apl_debugfs_conf),
+ TELEM_DEBUGFS_CPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS, telem_apl_debugfs_conf),
{}
};
diff --git a/drivers/platform/x86/intel_telemetry_pltdrv.c b/drivers/platform/x86/intel_telemetry_pltdrv.c
index 2f889d6c270e..fcc6bee51a42 100644
--- a/drivers/platform/x86/intel_telemetry_pltdrv.c
+++ b/drivers/platform/x86/intel_telemetry_pltdrv.c
@@ -192,7 +192,7 @@ static struct telemetry_plt_config telem_glk_config = {
static const struct x86_cpu_id telemetry_cpu_ids[] = {
TELEM_CPU(INTEL_FAM6_ATOM_GOLDMONT, telem_apl_config),
- TELEM_CPU(INTEL_FAM6_ATOM_GEMINI_LAKE, telem_glk_config),
+ TELEM_CPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS, telem_glk_config),
{}
};
diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index 295d8dcba48c..8cbfcce57a06 100644
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -1164,13 +1164,13 @@ static const struct x86_cpu_id rapl_ids[] __initconst = {
RAPL_CPU(INTEL_FAM6_KABYLAKE_DESKTOP, rapl_defaults_core),
RAPL_CPU(INTEL_FAM6_CANNONLAKE_MOBILE, rapl_defaults_core),
- RAPL_CPU(INTEL_FAM6_ATOM_SILVERMONT1, rapl_defaults_byt),
+ RAPL_CPU(INTEL_FAM6_ATOM_SILVERMONT, rapl_defaults_byt),
RAPL_CPU(INTEL_FAM6_ATOM_AIRMONT, rapl_defaults_cht),
- RAPL_CPU(INTEL_FAM6_ATOM_MERRIFIELD, rapl_defaults_tng),
- RAPL_CPU(INTEL_FAM6_ATOM_MOOREFIELD, rapl_defaults_ann),
+ RAPL_CPU(INTEL_FAM6_ATOM_SILVERMONT_MID, rapl_defaults_tng),
+ RAPL_CPU(INTEL_FAM6_ATOM_AIRMONT_MID, rapl_defaults_ann),
RAPL_CPU(INTEL_FAM6_ATOM_GOLDMONT, rapl_defaults_core),
- RAPL_CPU(INTEL_FAM6_ATOM_GEMINI_LAKE, rapl_defaults_core),
- RAPL_CPU(INTEL_FAM6_ATOM_DENVERTON, rapl_defaults_core),
+ RAPL_CPU(INTEL_FAM6_ATOM_GOLDMONT_PLUS, rapl_defaults_core),
+ RAPL_CPU(INTEL_FAM6_ATOM_GOLDMONT_X, rapl_defaults_core),
RAPL_CPU(INTEL_FAM6_XEON_PHI_KNL, rapl_defaults_hsw_server),
RAPL_CPU(INTEL_FAM6_XEON_PHI_KNM, rapl_defaults_hsw_server),
diff --git a/drivers/thermal/intel_soc_dts_thermal.c b/drivers/thermal/intel_soc_dts_thermal.c
index 1e47511a6bd5..d748527d7a38 100644
--- a/drivers/thermal/intel_soc_dts_thermal.c
+++ b/drivers/thermal/intel_soc_dts_thermal.c
@@ -45,7 +45,7 @@ static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
}
static const struct x86_cpu_id soc_thermal_ids[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1, 0,
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT, 0,
BYT_SOC_DTS_APIC_IRQ},
{}
};
diff --git a/sound/soc/intel/boards/bytcr_rt5651.c b/sound/soc/intel/boards/bytcr_rt5651.c
index b74bbee111c6..c6c8d20be1d2 100644
--- a/sound/soc/intel/boards/bytcr_rt5651.c
+++ b/sound/soc/intel/boards/bytcr_rt5651.c
@@ -787,7 +787,7 @@ static struct snd_soc_card byt_rt5651_card = {
};
static const struct x86_cpu_id baytrail_cpu_ids[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 }, /* Valleyview */
+ { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT }, /* Valleyview */
{}
};
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 83964f796edb..fbb53c952b73 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -2082,7 +2082,7 @@ int has_turbo_ratio_group_limits(int family, int model)
switch (model) {
case INTEL_FAM6_ATOM_GOLDMONT:
case INTEL_FAM6_SKYLAKE_X:
- case INTEL_FAM6_ATOM_DENVERTON:
+ case INTEL_FAM6_ATOM_GOLDMONT_X:
return 1;
}
return 0;
@@ -3149,9 +3149,9 @@ int probe_nhm_msrs(unsigned int family, unsigned int model)
pkg_cstate_limits = skx_pkg_cstate_limits;
has_misc_feature_control = 1;
break;
- case INTEL_FAM6_ATOM_SILVERMONT1: /* BYT */
+ case INTEL_FAM6_ATOM_SILVERMONT: /* BYT */
no_MSR_MISC_PWR_MGMT = 1;
- case INTEL_FAM6_ATOM_SILVERMONT2: /* AVN */
+ case INTEL_FAM6_ATOM_SILVERMONT_X: /* AVN */
pkg_cstate_limits = slv_pkg_cstate_limits;
break;
case INTEL_FAM6_ATOM_AIRMONT: /* AMT */
@@ -3163,8 +3163,8 @@ int probe_nhm_msrs(unsigned int family, unsigned int model)
pkg_cstate_limits = phi_pkg_cstate_limits;
break;
case INTEL_FAM6_ATOM_GOLDMONT: /* BXT */
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
- case INTEL_FAM6_ATOM_DENVERTON: /* DNV */
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
+ case INTEL_FAM6_ATOM_GOLDMONT_X: /* DNV */
pkg_cstate_limits = bxt_pkg_cstate_limits;
break;
default:
@@ -3193,9 +3193,9 @@ int has_slv_msrs(unsigned int family, unsigned int model)
return 0;
switch (model) {
- case INTEL_FAM6_ATOM_SILVERMONT1:
- case INTEL_FAM6_ATOM_MERRIFIELD:
- case INTEL_FAM6_ATOM_MOOREFIELD:
+ case INTEL_FAM6_ATOM_SILVERMONT:
+ case INTEL_FAM6_ATOM_SILVERMONT_MID:
+ case INTEL_FAM6_ATOM_AIRMONT_MID:
return 1;
}
return 0;
@@ -3207,7 +3207,7 @@ int is_dnv(unsigned int family, unsigned int model)
return 0;
switch (model) {
- case INTEL_FAM6_ATOM_DENVERTON:
+ case INTEL_FAM6_ATOM_GOLDMONT_X:
return 1;
}
return 0;
@@ -3724,8 +3724,8 @@ double get_tdp(unsigned int model)
return ((msr >> 0) & RAPL_POWER_GRANULARITY) * rapl_power_units;
switch (model) {
- case INTEL_FAM6_ATOM_SILVERMONT1:
- case INTEL_FAM6_ATOM_SILVERMONT2:
+ case INTEL_FAM6_ATOM_SILVERMONT:
+ case INTEL_FAM6_ATOM_SILVERMONT_X:
return 30.0;
default:
return 135.0;
@@ -3791,7 +3791,7 @@ void rapl_probe(unsigned int family, unsigned int model)
}
break;
case INTEL_FAM6_ATOM_GOLDMONT: /* BXT */
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
do_rapl = RAPL_PKG | RAPL_PKG_POWER_INFO;
if (rapl_joules)
BIC_PRESENT(BIC_Pkg_J);
@@ -3850,8 +3850,8 @@ void rapl_probe(unsigned int family, unsigned int model)
BIC_PRESENT(BIC_RAMWatt);
}
break;
- case INTEL_FAM6_ATOM_SILVERMONT1: /* BYT */
- case INTEL_FAM6_ATOM_SILVERMONT2: /* AVN */
+ case INTEL_FAM6_ATOM_SILVERMONT: /* BYT */
+ case INTEL_FAM6_ATOM_SILVERMONT_X: /* AVN */
do_rapl = RAPL_PKG | RAPL_CORES;
if (rapl_joules) {
BIC_PRESENT(BIC_Pkg_J);
@@ -3861,7 +3861,7 @@ void rapl_probe(unsigned int family, unsigned int model)
BIC_PRESENT(BIC_CorWatt);
}
break;
- case INTEL_FAM6_ATOM_DENVERTON: /* DNV */
+ case INTEL_FAM6_ATOM_GOLDMONT_X: /* DNV */
do_rapl = RAPL_PKG | RAPL_DRAM | RAPL_DRAM_POWER_INFO | RAPL_DRAM_PERF_STATUS | RAPL_PKG_PERF_STATUS | RAPL_PKG_POWER_INFO | RAPL_CORES_ENERGY_STATUS;
BIC_PRESENT(BIC_PKG__);
BIC_PRESENT(BIC_RAM__);
@@ -3884,7 +3884,7 @@ void rapl_probe(unsigned int family, unsigned int model)
return;
rapl_power_units = 1.0 / (1 << (msr & 0xF));
- if (model == INTEL_FAM6_ATOM_SILVERMONT1)
+ if (model == INTEL_FAM6_ATOM_SILVERMONT)
rapl_energy_units = 1.0 * (1 << (msr >> 8 & 0x1F)) / 1000000;
else
rapl_energy_units = 1.0 / (1 << (msr >> 8 & 0x1F));
@@ -4141,8 +4141,8 @@ int has_snb_msrs(unsigned int family, unsigned int model)
case INTEL_FAM6_CANNONLAKE_MOBILE: /* CNL */
case INTEL_FAM6_SKYLAKE_X: /* SKX */
case INTEL_FAM6_ATOM_GOLDMONT: /* BXT */
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
- case INTEL_FAM6_ATOM_DENVERTON: /* DNV */
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
+ case INTEL_FAM6_ATOM_GOLDMONT_X: /* DNV */
return 1;
}
return 0;
@@ -4174,7 +4174,7 @@ int has_hsw_msrs(unsigned int family, unsigned int model)
case INTEL_FAM6_KABYLAKE_DESKTOP: /* KBL */
case INTEL_FAM6_CANNONLAKE_MOBILE: /* CNL */
case INTEL_FAM6_ATOM_GOLDMONT: /* BXT */
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
return 1;
}
return 0;
@@ -4209,8 +4209,8 @@ int is_slm(unsigned int family, unsigned int model)
if (!genuine_intel)
return 0;
switch (model) {
- case INTEL_FAM6_ATOM_SILVERMONT1: /* BYT */
- case INTEL_FAM6_ATOM_SILVERMONT2: /* AVN */
+ case INTEL_FAM6_ATOM_SILVERMONT: /* BYT */
+ case INTEL_FAM6_ATOM_SILVERMONT_X: /* AVN */
return 1;
}
return 0;
@@ -4581,11 +4581,11 @@ void process_cpuid()
case INTEL_FAM6_KABYLAKE_DESKTOP: /* KBL */
crystal_hz = 24000000; /* 24.0 MHz */
break;
- case INTEL_FAM6_ATOM_DENVERTON: /* DNV */
+ case INTEL_FAM6_ATOM_GOLDMONT_X: /* DNV */
crystal_hz = 25000000; /* 25.0 MHz */
break;
case INTEL_FAM6_ATOM_GOLDMONT: /* BXT */
- case INTEL_FAM6_ATOM_GEMINI_LAKE:
+ case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
crystal_hz = 19200000; /* 19.2 MHz */
break;
default:

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@ -0,0 +1,48 @@
From e75df51aa9a06da683ae47809b52e1987d2824f8 Mon Sep 17 00:00:00 2001
From: Eduardo Habkost <ehabkost@redhat.com>
Date: Wed, 5 Dec 2018 17:19:56 -0200
Subject: [PATCH 03/30] kvm: x86: Report STIBP on GET_SUPPORTED_CPUID
commit d7b09c827a6cf291f66637a36f46928dd1423184 upstream
Months ago, we have added code to allow direct access to MSR_IA32_SPEC_CTRL
to the guest, which makes STIBP available to guests. This was implemented
by commits d28b387fb74d ("KVM/VMX: Allow direct access to
MSR_IA32_SPEC_CTRL") and b2ac58f90540 ("KVM/SVM: Allow direct access to
MSR_IA32_SPEC_CTRL").
However, we never updated GET_SUPPORTED_CPUID to let userspace know that
STIBP can be enabled in CPUID. Fix that by updating
kvm_cpuid_8000_0008_ebx_x86_features and kvm_cpuid_7_0_edx_x86_features.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kvm/cpuid.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 98d13c6a64be..fe9907517fb4 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -382,7 +382,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 0x80000008.ebx */
const u32 kvm_cpuid_8000_0008_ebx_x86_features =
F(AMD_IBPB) | F(AMD_IBRS) | F(AMD_SSBD) | F(VIRT_SSBD) |
- F(AMD_SSB_NO);
+ F(AMD_SSB_NO) | F(AMD_STIBP);
/* cpuid 0xC0000001.edx */
const u32 kvm_cpuid_C000_0001_edx_x86_features =
@@ -412,7 +412,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 7.0.edx*/
const u32 kvm_cpuid_7_0_edx_x86_features =
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
- F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES);
+ F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP);
/* all calls to cpuid_count() should be made on the same cpu */
get_cpu();

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@ -0,0 +1,119 @@
From de787f2bb763b7b5516f5c43df2e9c63be6ef279 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 21 Feb 2019 12:36:50 +0100
Subject: [PATCH 04/30] x86/msr-index: Cleanup bit defines
commit d8eabc37310a92df40d07c5a8afc53cebf996716 upstream
Greg pointed out that speculation related bit defines are using (1 << N)
format instead of BIT(N). Aside of that (1 << N) is wrong as it should use
1UL at least.
Clean it up.
[ Josh Poimboeuf: Fix tools build ]
Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/include/asm/msr-index.h | 34 ++++++++++---------
tools/power/x86/turbostat/Makefile | 2 +-
.../power/x86/x86_energy_perf_policy/Makefile | 2 +-
3 files changed, 20 insertions(+), 18 deletions(-)
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index f14ca0be1e3f..308b7c94df00 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -2,6 +2,8 @@
#ifndef _ASM_X86_MSR_INDEX_H
#define _ASM_X86_MSR_INDEX_H
+#include <linux/bits.h>
+
/*
* CPU model specific register (MSR) numbers.
*
@@ -40,14 +42,14 @@
/* Intel MSRs. Some also available on other CPUs */
#define MSR_IA32_SPEC_CTRL 0x00000048 /* Speculation Control */
-#define SPEC_CTRL_IBRS (1 << 0) /* Indirect Branch Restricted Speculation */
+#define SPEC_CTRL_IBRS BIT(0) /* Indirect Branch Restricted Speculation */
#define SPEC_CTRL_STIBP_SHIFT 1 /* Single Thread Indirect Branch Predictor (STIBP) bit */
-#define SPEC_CTRL_STIBP (1 << SPEC_CTRL_STIBP_SHIFT) /* STIBP mask */
+#define SPEC_CTRL_STIBP BIT(SPEC_CTRL_STIBP_SHIFT) /* STIBP mask */
#define SPEC_CTRL_SSBD_SHIFT 2 /* Speculative Store Bypass Disable bit */
-#define SPEC_CTRL_SSBD (1 << SPEC_CTRL_SSBD_SHIFT) /* Speculative Store Bypass Disable */
+#define SPEC_CTRL_SSBD BIT(SPEC_CTRL_SSBD_SHIFT) /* Speculative Store Bypass Disable */
#define MSR_IA32_PRED_CMD 0x00000049 /* Prediction Command */
-#define PRED_CMD_IBPB (1 << 0) /* Indirect Branch Prediction Barrier */
+#define PRED_CMD_IBPB BIT(0) /* Indirect Branch Prediction Barrier */
#define MSR_PPIN_CTL 0x0000004e
#define MSR_PPIN 0x0000004f
@@ -69,20 +71,20 @@
#define MSR_MTRRcap 0x000000fe
#define MSR_IA32_ARCH_CAPABILITIES 0x0000010a
-#define ARCH_CAP_RDCL_NO (1 << 0) /* Not susceptible to Meltdown */
-#define ARCH_CAP_IBRS_ALL (1 << 1) /* Enhanced IBRS support */
-#define ARCH_CAP_SKIP_VMENTRY_L1DFLUSH (1 << 3) /* Skip L1D flush on vmentry */
-#define ARCH_CAP_SSB_NO (1 << 4) /*
- * Not susceptible to Speculative Store Bypass
- * attack, so no Speculative Store Bypass
- * control required.
- */
+#define ARCH_CAP_RDCL_NO BIT(0) /* Not susceptible to Meltdown */
+#define ARCH_CAP_IBRS_ALL BIT(1) /* Enhanced IBRS support */
+#define ARCH_CAP_SKIP_VMENTRY_L1DFLUSH BIT(3) /* Skip L1D flush on vmentry */
+#define ARCH_CAP_SSB_NO BIT(4) /*
+ * Not susceptible to Speculative Store Bypass
+ * attack, so no Speculative Store Bypass
+ * control required.
+ */
#define MSR_IA32_FLUSH_CMD 0x0000010b
-#define L1D_FLUSH (1 << 0) /*
- * Writeback and invalidate the
- * L1 data cache.
- */
+#define L1D_FLUSH BIT(0) /*
+ * Writeback and invalidate the
+ * L1 data cache.
+ */
#define MSR_IA32_BBL_CR_CTL 0x00000119
#define MSR_IA32_BBL_CR_CTL3 0x0000011e
diff --git a/tools/power/x86/turbostat/Makefile b/tools/power/x86/turbostat/Makefile
index 2ab25aa38263..ff058bfbca3e 100644
--- a/tools/power/x86/turbostat/Makefile
+++ b/tools/power/x86/turbostat/Makefile
@@ -9,7 +9,7 @@ ifeq ("$(origin O)", "command line")
endif
turbostat : turbostat.c
-CFLAGS += -Wall
+CFLAGS += -Wall -I../../../include
CFLAGS += -DMSRHEADER='"../../../../arch/x86/include/asm/msr-index.h"'
CFLAGS += -DINTEL_FAMILY_HEADER='"../../../../arch/x86/include/asm/intel-family.h"'
diff --git a/tools/power/x86/x86_energy_perf_policy/Makefile b/tools/power/x86/x86_energy_perf_policy/Makefile
index f4534fb8b951..da781b430937 100644
--- a/tools/power/x86/x86_energy_perf_policy/Makefile
+++ b/tools/power/x86/x86_energy_perf_policy/Makefile
@@ -9,7 +9,7 @@ ifeq ("$(origin O)", "command line")
endif
x86_energy_perf_policy : x86_energy_perf_policy.c
-CFLAGS += -Wall
+CFLAGS += -Wall -I../../../include
CFLAGS += -DMSRHEADER='"../../../../arch/x86/include/asm/msr-index.h"'
%: %.c

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@ -0,0 +1,169 @@
From bb9d4a24ba55d1487a34d287c6b940ce00b85822 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 27 Feb 2019 10:10:23 +0100
Subject: [PATCH 05/30] x86/speculation: Consolidate CPU whitelists
commit 36ad35131adacc29b328b9c8b6277a8bf0d6fd5d upstream
The CPU vulnerability whitelists have some overlap and there are more
whitelists coming along.
Use the driver_data field in the x86_cpu_id struct to denote the
whitelisted vulnerabilities and combine all whitelists into one.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/kernel/cpu/common.c | 105 +++++++++++++++++++----------------
1 file changed, 56 insertions(+), 49 deletions(-)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 10e5ccfa9278..fd16b4cc991f 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -948,60 +948,68 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#endif
}
-static const __initconst struct x86_cpu_id cpu_no_speculation[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL_TABLET, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_BONNELL_MID, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SALTWELL_MID, X86_FEATURE_ANY },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_BONNELL, X86_FEATURE_ANY },
- { X86_VENDOR_CENTAUR, 5 },
- { X86_VENDOR_INTEL, 5 },
- { X86_VENDOR_NSC, 5 },
- { X86_VENDOR_ANY, 4 },
+#define NO_SPECULATION BIT(0)
+#define NO_MELTDOWN BIT(1)
+#define NO_SSB BIT(2)
+#define NO_L1TF BIT(3)
+
+#define VULNWL(_vendor, _family, _model, _whitelist) \
+ { X86_VENDOR_##_vendor, _family, _model, X86_FEATURE_ANY, _whitelist }
+
+#define VULNWL_INTEL(model, whitelist) \
+ VULNWL(INTEL, 6, INTEL_FAM6_##model, whitelist)
+
+#define VULNWL_AMD(family, whitelist) \
+ VULNWL(AMD, family, X86_MODEL_ANY, whitelist)
+
+static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
+ VULNWL(ANY, 4, X86_MODEL_ANY, NO_SPECULATION),
+ VULNWL(CENTAUR, 5, X86_MODEL_ANY, NO_SPECULATION),
+ VULNWL(INTEL, 5, X86_MODEL_ANY, NO_SPECULATION),
+ VULNWL(NSC, 5, X86_MODEL_ANY, NO_SPECULATION),
+
+ VULNWL_INTEL(ATOM_SALTWELL, NO_SPECULATION),
+ VULNWL_INTEL(ATOM_SALTWELL_TABLET, NO_SPECULATION),
+ VULNWL_INTEL(ATOM_SALTWELL_MID, NO_SPECULATION),
+ VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION),
+ VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION),
+
+ VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(ATOM_SILVERMONT_X, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF),
+
+ VULNWL_INTEL(CORE_YONAH, NO_SSB),
+
+ VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT, NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT_X, NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_L1TF),
+
+ VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF),
+ VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF),
+ VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF),
+ VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF),
+
+ /* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */
+ VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF),
{}
};
-static const __initconst struct x86_cpu_id cpu_no_meltdown[] = {
- { X86_VENDOR_AMD },
- {}
-};
-
-/* Only list CPUs which speculate but are non susceptible to SSB */
-static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_X },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_MID },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
- { X86_VENDOR_AMD, 0x12, },
- { X86_VENDOR_AMD, 0x11, },
- { X86_VENDOR_AMD, 0x10, },
- { X86_VENDOR_AMD, 0xf, },
- {}
-};
+static bool __init cpu_matches(unsigned long which)
+{
+ const struct x86_cpu_id *m = x86_match_cpu(cpu_vuln_whitelist);
-static const __initconst struct x86_cpu_id cpu_no_l1tf[] = {
- /* in addition to cpu_no_speculation */
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_X },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT_MID },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT_MID },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT_X },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_GOLDMONT_PLUS },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
- { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
- {}
-};
+ return m && !!(m->driver_data & which);
+}
static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
{
u64 ia32_cap = 0;
- if (x86_match_cpu(cpu_no_speculation))
+ if (cpu_matches(NO_SPECULATION))
return;
setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
@@ -1010,15 +1018,14 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
- if (!x86_match_cpu(cpu_no_spec_store_bypass) &&
- !(ia32_cap & ARCH_CAP_SSB_NO) &&
+ if (!cpu_matches(NO_SSB) && !(ia32_cap & ARCH_CAP_SSB_NO) &&
!cpu_has(c, X86_FEATURE_AMD_SSB_NO))
setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
if (ia32_cap & ARCH_CAP_IBRS_ALL)
setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
- if (x86_match_cpu(cpu_no_meltdown))
+ if (cpu_matches(NO_MELTDOWN))
return;
/* Rogue Data Cache Load? No! */
@@ -1027,7 +1034,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
- if (x86_match_cpu(cpu_no_l1tf))
+ if (cpu_matches(NO_L1TF))
return;
setup_force_cpu_bug(X86_BUG_L1TF);

View File

@ -0,0 +1,154 @@
From e082f3653d17755854a3538e5658061ac92e2ab3 Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@linux.intel.com>
Date: Fri, 18 Jan 2019 16:50:16 -0800
Subject: [PATCH 06/30] x86/speculation/mds: Add basic bug infrastructure for
MDS
commit ed5194c2732c8084af9fd159c146ea92bf137128 upstream
Microarchitectural Data Sampling (MDS), is a class of side channel attacks
on internal buffers in Intel CPUs. The variants are:
- Microarchitectural Store Buffer Data Sampling (MSBDS) (CVE-2018-12126)
- Microarchitectural Fill Buffer Data Sampling (MFBDS) (CVE-2018-12130)
- Microarchitectural Load Port Data Sampling (MLPDS) (CVE-2018-12127)
MSBDS leaks Store Buffer Entries which can be speculatively forwarded to a
dependent load (store-to-load forwarding) as an optimization. The forward
can also happen to a faulting or assisting load operation for a different
memory address, which can be exploited under certain conditions. Store
buffers are partitioned between Hyper-Threads so cross thread forwarding is
not possible. But if a thread enters or exits a sleep state the store
buffer is repartitioned which can expose data from one thread to the other.
MFBDS leaks Fill Buffer Entries. Fill buffers are used internally to manage
L1 miss situations and to hold data which is returned or sent in response
to a memory or I/O operation. Fill buffers can forward data to a load
operation and also write data to the cache. When the fill buffer is
deallocated it can retain the stale data of the preceding operations which
can then be forwarded to a faulting or assisting load operation, which can
be exploited under certain conditions. Fill buffers are shared between
Hyper-Threads so cross thread leakage is possible.
MLDPS leaks Load Port Data. Load ports are used to perform load operations
from memory or I/O. The received data is then forwarded to the register
file or a subsequent operation. In some implementations the Load Port can
contain stale data from a previous operation which can be forwarded to
faulting or assisting loads under certain conditions, which again can be
exploited eventually. Load ports are shared between Hyper-Threads so cross
thread leakage is possible.
All variants have the same mitigation for single CPU thread case (SMT off),
so the kernel can treat them as one MDS issue.
Add the basic infrastructure to detect if the current CPU is affected by
MDS.
[ tglx: Rewrote changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/include/asm/cpufeatures.h | 2 ++
arch/x86/include/asm/msr-index.h | 5 +++++
arch/x86/kernel/cpu/common.c | 23 +++++++++++++++--------
3 files changed, 22 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 7b31ee5223fc..1dc7b8129b55 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -341,6 +341,7 @@
#define X86_FEATURE_AVX512_4VNNIW (18*32+ 2) /* AVX-512 Neural Network Instructions */
#define X86_FEATURE_AVX512_4FMAPS (18*32+ 3) /* AVX-512 Multiply Accumulation Single precision */
#define X86_FEATURE_TSX_FORCE_ABORT (18*32+13) /* "" TSX_FORCE_ABORT */
+#define X86_FEATURE_MD_CLEAR (18*32+10) /* VERW clears CPU buffers */
#define X86_FEATURE_PCONFIG (18*32+18) /* Intel PCONFIG */
#define X86_FEATURE_SPEC_CTRL (18*32+26) /* "" Speculation Control (IBRS + IBPB) */
#define X86_FEATURE_INTEL_STIBP (18*32+27) /* "" Single Thread Indirect Branch Predictors */
@@ -378,5 +379,6 @@
#define X86_BUG_SPECTRE_V2 X86_BUG(16) /* CPU is affected by Spectre variant 2 attack with indirect branches */
#define X86_BUG_SPEC_STORE_BYPASS X86_BUG(17) /* CPU is affected by speculative store bypass attack */
#define X86_BUG_L1TF X86_BUG(18) /* CPU is affected by L1 Terminal Fault */
+#define X86_BUG_MDS X86_BUG(19) /* CPU is affected by Microarchitectural data sampling */
#endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 308b7c94df00..f85f43db9225 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -79,6 +79,11 @@
* attack, so no Speculative Store Bypass
* control required.
*/
+#define ARCH_CAP_MDS_NO BIT(5) /*
+ * Not susceptible to
+ * Microarchitectural Data
+ * Sampling (MDS) vulnerabilities.
+ */
#define MSR_IA32_FLUSH_CMD 0x0000010b
#define L1D_FLUSH BIT(0) /*
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index fd16b4cc991f..0ea1e4bc3e20 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -952,6 +952,7 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#define NO_MELTDOWN BIT(1)
#define NO_SSB BIT(2)
#define NO_L1TF BIT(3)
+#define NO_MDS BIT(4)
#define VULNWL(_vendor, _family, _model, _whitelist) \
{ X86_VENDOR_##_vendor, _family, _model, X86_FEATURE_ANY, _whitelist }
@@ -968,6 +969,7 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL(INTEL, 5, X86_MODEL_ANY, NO_SPECULATION),
VULNWL(NSC, 5, X86_MODEL_ANY, NO_SPECULATION),
+ /* Intel Family 6 */
VULNWL_INTEL(ATOM_SALTWELL, NO_SPECULATION),
VULNWL_INTEL(ATOM_SALTWELL_TABLET, NO_SPECULATION),
VULNWL_INTEL(ATOM_SALTWELL_MID, NO_SPECULATION),
@@ -984,17 +986,19 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL_INTEL(CORE_YONAH, NO_SSB),
VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF),
- VULNWL_INTEL(ATOM_GOLDMONT, NO_L1TF),
- VULNWL_INTEL(ATOM_GOLDMONT_X, NO_L1TF),
- VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_L1TF),
- VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF),
- VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF),
- VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF),
- VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT, NO_MDS | NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT_X, NO_MDS | NO_L1TF),
+ VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_MDS | NO_L1TF),
+
+ /* AMD Family 0xf - 0x12 */
+ VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS),
+ VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS),
+ VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS),
+ VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS),
/* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */
- VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF),
+ VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS),
{}
};
@@ -1025,6 +1029,9 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
if (ia32_cap & ARCH_CAP_IBRS_ALL)
setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
+ if (!cpu_matches(NO_MDS) && !(ia32_cap & ARCH_CAP_MDS_NO))
+ setup_force_cpu_bug(X86_BUG_MDS);
+
if (cpu_matches(NO_MELTDOWN))
return;

View File

@ -0,0 +1,90 @@
From 91439bd017c726a81577dd2bee789580f5bfdf35 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Fri, 1 Mar 2019 20:21:08 +0100
Subject: [PATCH 07/30] x86/speculation/mds: Add BUG_MSBDS_ONLY
commit e261f209c3666e842fd645a1e31f001c3a26def9 upstream
This bug bit is set on CPUs which are only affected by Microarchitectural
Store Buffer Data Sampling (MSBDS) and not by any other MDS variant.
This is important because the Store Buffers are partitioned between
Hyper-Threads so cross thread forwarding is not possible. But if a thread
enters or exits a sleep state the store buffer is repartitioned which can
expose data from one thread to the other. This transition can be mitigated.
That means that for CPUs which are only affected by MSBDS SMT can be
enabled, if the CPU is not affected by other SMT sensitive vulnerabilities,
e.g. L1TF. The XEON PHI variants fall into that category. Also the
Silvermont/Airmont ATOMs, but for them it's not really relevant as they do
not support SMT, but mark them for completeness sake.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/kernel/cpu/common.c | 20 ++++++++++++--------
2 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 1dc7b8129b55..69037da75ea0 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -380,5 +380,6 @@
#define X86_BUG_SPEC_STORE_BYPASS X86_BUG(17) /* CPU is affected by speculative store bypass attack */
#define X86_BUG_L1TF X86_BUG(18) /* CPU is affected by L1 Terminal Fault */
#define X86_BUG_MDS X86_BUG(19) /* CPU is affected by Microarchitectural data sampling */
+#define X86_BUG_MSBDS_ONLY X86_BUG(20) /* CPU is only affected by the MSDBS variant of BUG_MDS */
#endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 0ea1e4bc3e20..1073118b9bf0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -953,6 +953,7 @@ static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
#define NO_SSB BIT(2)
#define NO_L1TF BIT(3)
#define NO_MDS BIT(4)
+#define MSBDS_ONLY BIT(5)
#define VULNWL(_vendor, _family, _model, _whitelist) \
{ X86_VENDOR_##_vendor, _family, _model, X86_FEATURE_ANY, _whitelist }
@@ -976,16 +977,16 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION),
VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION),
- VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF),
- VULNWL_INTEL(ATOM_SILVERMONT_X, NO_SSB | NO_L1TF),
- VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF),
- VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF),
- VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF),
- VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF),
+ VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(ATOM_SILVERMONT_X, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF | MSBDS_ONLY),
+ VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF | MSBDS_ONLY),
VULNWL_INTEL(CORE_YONAH, NO_SSB),
- VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF),
+ VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF | MSBDS_ONLY),
VULNWL_INTEL(ATOM_GOLDMONT, NO_MDS | NO_L1TF),
VULNWL_INTEL(ATOM_GOLDMONT_X, NO_MDS | NO_L1TF),
@@ -1029,8 +1030,11 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
if (ia32_cap & ARCH_CAP_IBRS_ALL)
setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
- if (!cpu_matches(NO_MDS) && !(ia32_cap & ARCH_CAP_MDS_NO))
+ if (!cpu_matches(NO_MDS) && !(ia32_cap & ARCH_CAP_MDS_NO)) {
setup_force_cpu_bug(X86_BUG_MDS);
+ if (cpu_matches(MSBDS_ONLY))
+ setup_force_cpu_bug(X86_BUG_MSBDS_ONLY);
+ }
if (cpu_matches(NO_MELTDOWN))
return;

View File

@ -0,0 +1,43 @@
From 10c46ffb2f76b9a73f070877b3e83b9096bf0ed8 Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@linux.intel.com>
Date: Fri, 18 Jan 2019 16:50:23 -0800
Subject: [PATCH 08/30] x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
commit 6c4dbbd14730c43f4ed808a9c42ca41625925c22 upstream
X86_FEATURE_MD_CLEAR is a new CPUID bit which is set when microcode
provides the mechanism to invoke a flush of various exploitable CPU buffers
by invoking the VERW instruction.
Hand it through to guests so they can adjust their mitigations.
This also requires corresponding qemu changes, which are available
separately.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/kvm/cpuid.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index fe9907517fb4..b810102a9cfa 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -412,7 +412,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
/* cpuid 7.0.edx*/
const u32 kvm_cpuid_7_0_edx_x86_features =
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
- F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP);
+ F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP) |
+ F(MD_CLEAR);
/* all calls to cpuid_count() should be made on the same cpu */
get_cpu();

View File

@ -0,0 +1,231 @@
From 370fbb129df726c669be7f89403d7b2053f035bc Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 18 Feb 2019 23:13:06 +0100
Subject: [PATCH 09/30] x86/speculation/mds: Add mds_clear_cpu_buffers()
commit 6a9e529272517755904b7afa639f6db59ddb793e upstream
The Microarchitectural Data Sampling (MDS) vulernabilities are mitigated by
clearing the affected CPU buffers. The mechanism for clearing the buffers
uses the unused and obsolete VERW instruction in combination with a
microcode update which triggers a CPU buffer clear when VERW is executed.
Provide a inline function with the assembly magic. The argument of the VERW
instruction must be a memory operand as documented:
"MD_CLEAR enumerates that the memory-operand variant of VERW (for
example, VERW m16) has been extended to also overwrite buffers affected
by MDS. This buffer overwriting functionality is not guaranteed for the
register operand variant of VERW."
Documentation also recommends to use a writable data segment selector:
"The buffer overwriting occurs regardless of the result of the VERW
permission check, as well as when the selector is null or causes a
descriptor load segment violation. However, for lowest latency we
recommend using a selector that indicates a valid writable data
segment."
Add x86 specific documentation about MDS and the internal workings of the
mitigation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
Documentation/index.rst | 1 +
Documentation/x86/conf.py | 10 +++
Documentation/x86/index.rst | 8 +++
Documentation/x86/mds.rst | 99 ++++++++++++++++++++++++++++
arch/x86/include/asm/nospec-branch.h | 25 +++++++
5 files changed, 143 insertions(+)
create mode 100644 Documentation/x86/conf.py
create mode 100644 Documentation/x86/index.rst
create mode 100644 Documentation/x86/mds.rst
diff --git a/Documentation/index.rst b/Documentation/index.rst
index 5db7e87c7cb1..1cdc139adb40 100644
--- a/Documentation/index.rst
+++ b/Documentation/index.rst
@@ -104,6 +104,7 @@ implementation.
:maxdepth: 2
sh/index
+ x86/index
Filesystem Documentation
------------------------
diff --git a/Documentation/x86/conf.py b/Documentation/x86/conf.py
new file mode 100644
index 000000000000..33c5c3142e20
--- /dev/null
+++ b/Documentation/x86/conf.py
@@ -0,0 +1,10 @@
+# -*- coding: utf-8; mode: python -*-
+
+project = "X86 architecture specific documentation"
+
+tags.add("subproject")
+
+latex_documents = [
+ ('index', 'x86.tex', project,
+ 'The kernel development community', 'manual'),
+]
diff --git a/Documentation/x86/index.rst b/Documentation/x86/index.rst
new file mode 100644
index 000000000000..ef389dcf1b1d
--- /dev/null
+++ b/Documentation/x86/index.rst
@@ -0,0 +1,8 @@
+==========================
+x86 architecture specifics
+==========================
+
+.. toctree::
+ :maxdepth: 1
+
+ mds
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
new file mode 100644
index 000000000000..1096738d50f2
--- /dev/null
+++ b/Documentation/x86/mds.rst
@@ -0,0 +1,99 @@
+Microarchitectural Data Sampling (MDS) mitigation
+=================================================
+
+.. _mds:
+
+Overview
+--------
+
+Microarchitectural Data Sampling (MDS) is a family of side channel attacks
+on internal buffers in Intel CPUs. The variants are:
+
+ - Microarchitectural Store Buffer Data Sampling (MSBDS) (CVE-2018-12126)
+ - Microarchitectural Fill Buffer Data Sampling (MFBDS) (CVE-2018-12130)
+ - Microarchitectural Load Port Data Sampling (MLPDS) (CVE-2018-12127)
+
+MSBDS leaks Store Buffer Entries which can be speculatively forwarded to a
+dependent load (store-to-load forwarding) as an optimization. The forward
+can also happen to a faulting or assisting load operation for a different
+memory address, which can be exploited under certain conditions. Store
+buffers are partitioned between Hyper-Threads so cross thread forwarding is
+not possible. But if a thread enters or exits a sleep state the store
+buffer is repartitioned which can expose data from one thread to the other.
+
+MFBDS leaks Fill Buffer Entries. Fill buffers are used internally to manage
+L1 miss situations and to hold data which is returned or sent in response
+to a memory or I/O operation. Fill buffers can forward data to a load
+operation and also write data to the cache. When the fill buffer is
+deallocated it can retain the stale data of the preceding operations which
+can then be forwarded to a faulting or assisting load operation, which can
+be exploited under certain conditions. Fill buffers are shared between
+Hyper-Threads so cross thread leakage is possible.
+
+MLPDS leaks Load Port Data. Load ports are used to perform load operations
+from memory or I/O. The received data is then forwarded to the register
+file or a subsequent operation. In some implementations the Load Port can
+contain stale data from a previous operation which can be forwarded to
+faulting or assisting loads under certain conditions, which again can be
+exploited eventually. Load ports are shared between Hyper-Threads so cross
+thread leakage is possible.
+
+
+Exposure assumptions
+--------------------
+
+It is assumed that attack code resides in user space or in a guest with one
+exception. The rationale behind this assumption is that the code construct
+needed for exploiting MDS requires:
+
+ - to control the load to trigger a fault or assist
+
+ - to have a disclosure gadget which exposes the speculatively accessed
+ data for consumption through a side channel.
+
+ - to control the pointer through which the disclosure gadget exposes the
+ data
+
+The existence of such a construct in the kernel cannot be excluded with
+100% certainty, but the complexity involved makes it extremly unlikely.
+
+There is one exception, which is untrusted BPF. The functionality of
+untrusted BPF is limited, but it needs to be thoroughly investigated
+whether it can be used to create such a construct.
+
+
+Mitigation strategy
+-------------------
+
+All variants have the same mitigation strategy at least for the single CPU
+thread case (SMT off): Force the CPU to clear the affected buffers.
+
+This is achieved by using the otherwise unused and obsolete VERW
+instruction in combination with a microcode update. The microcode clears
+the affected CPU buffers when the VERW instruction is executed.
+
+For virtualization there are two ways to achieve CPU buffer
+clearing. Either the modified VERW instruction or via the L1D Flush
+command. The latter is issued when L1TF mitigation is enabled so the extra
+VERW can be avoided. If the CPU is not affected by L1TF then VERW needs to
+be issued.
+
+If the VERW instruction with the supplied segment selector argument is
+executed on a CPU without the microcode update there is no side effect
+other than a small number of pointlessly wasted CPU cycles.
+
+This does not protect against cross Hyper-Thread attacks except for MSBDS
+which is only exploitable cross Hyper-thread when one of the Hyper-Threads
+enters a C-state.
+
+The kernel provides a function to invoke the buffer clearing:
+
+ mds_clear_cpu_buffers()
+
+The mitigation is invoked on kernel/userspace, hypervisor/guest and C-state
+(idle) transitions.
+
+According to current knowledge additional mitigations inside the kernel
+itself are not required because the necessary gadgets to expose the leaked
+data cannot be controlled in a way which allows exploitation from malicious
+user space or VM guests.
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 032b6009baab..c022732e2cf9 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -317,6 +317,31 @@ DECLARE_STATIC_KEY_FALSE(switch_to_cond_stibp);
DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
+#include <asm/segment.h>
+
+/**
+ * mds_clear_cpu_buffers - Mitigation for MDS vulnerability
+ *
+ * This uses the otherwise unused and obsolete VERW instruction in
+ * combination with microcode which triggers a CPU buffer flush when the
+ * instruction is executed.
+ */
+static inline void mds_clear_cpu_buffers(void)
+{
+ static const u16 ds = __KERNEL_DS;
+
+ /*
+ * Has to be the memory-operand variant because only that
+ * guarantees the CPU buffer flush functionality according to
+ * documentation. The register-operand variant does not.
+ * Works with any segment selector, but a valid writable
+ * data segment is the fastest variant.
+ *
+ * "cc" clobber is required because VERW modifies ZF.
+ */
+ asm volatile("verw %[ds]" : : [ds] "m" (ds) : "cc");
+}
+
#endif /* __ASSEMBLY__ */
/*

View File

@ -0,0 +1,203 @@
From d526a5f8b2e39468b2c2e88ae2ff01b4fb86a945 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 18 Feb 2019 23:42:51 +0100
Subject: [PATCH 10/30] x86/speculation/mds: Clear CPU buffers on exit to user
commit 04dcbdb8057827b043b3c71aa397c4c63e67d086 upstream
Add a static key which controls the invocation of the CPU buffer clear
mechanism on exit to user space and add the call into
prepare_exit_to_usermode() and do_nmi() right before actually returning.
Add documentation which kernel to user space transition this covers and
explain why some corner cases are not mitigated.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
Documentation/x86/mds.rst | 52 ++++++++++++++++++++++++++++
arch/x86/entry/common.c | 3 ++
arch/x86/include/asm/nospec-branch.h | 13 +++++++
arch/x86/kernel/cpu/bugs.c | 3 ++
arch/x86/kernel/nmi.c | 4 +++
arch/x86/kernel/traps.c | 8 +++++
6 files changed, 83 insertions(+)
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 1096738d50f2..54d935bf283b 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -97,3 +97,55 @@ According to current knowledge additional mitigations inside the kernel
itself are not required because the necessary gadgets to expose the leaked
data cannot be controlled in a way which allows exploitation from malicious
user space or VM guests.
+
+Mitigation points
+-----------------
+
+1. Return to user space
+^^^^^^^^^^^^^^^^^^^^^^^
+
+ When transitioning from kernel to user space the CPU buffers are flushed
+ on affected CPUs when the mitigation is not disabled on the kernel
+ command line. The migitation is enabled through the static key
+ mds_user_clear.
+
+ The mitigation is invoked in prepare_exit_to_usermode() which covers
+ most of the kernel to user space transitions. There are a few exceptions
+ which are not invoking prepare_exit_to_usermode() on return to user
+ space. These exceptions use the paranoid exit code.
+
+ - Non Maskable Interrupt (NMI):
+
+ Access to sensible data like keys, credentials in the NMI context is
+ mostly theoretical: The CPU can do prefetching or execute a
+ misspeculated code path and thereby fetching data which might end up
+ leaking through a buffer.
+
+ But for mounting other attacks the kernel stack address of the task is
+ already valuable information. So in full mitigation mode, the NMI is
+ mitigated on the return from do_nmi() to provide almost complete
+ coverage.
+
+ - Double fault (#DF):
+
+ A double fault is usually fatal, but the ESPFIX workaround, which can
+ be triggered from user space through modify_ldt(2) is a recoverable
+ double fault. #DF uses the paranoid exit path, so explicit mitigation
+ in the double fault handler is required.
+
+ - Machine Check Exception (#MC):
+
+ Another corner case is a #MC which hits between the CPU buffer clear
+ invocation and the actual return to user. As this still is in kernel
+ space it takes the paranoid exit path which does not clear the CPU
+ buffers. So the #MC handler repopulates the buffers to some
+ extent. Machine checks are not reliably controllable and the window is
+ extremly small so mitigation would just tick a checkbox that this
+ theoretical corner case is covered. To keep the amount of special
+ cases small, ignore #MC.
+
+ - Debug Exception (#DB):
+
+ This takes the paranoid exit path only when the INT1 breakpoint is in
+ kernel space. #DB on a user space address takes the regular exit path,
+ so no extra mitigation required.
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 3b2490b81918..8353348ddeaf 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -31,6 +31,7 @@
#include <asm/vdso.h>
#include <linux/uaccess.h>
#include <asm/cpufeature.h>
+#include <asm/nospec-branch.h>
#define CREATE_TRACE_POINTS
#include <trace/events/syscalls.h>
@@ -212,6 +213,8 @@ __visible inline void prepare_exit_to_usermode(struct pt_regs *regs)
#endif
user_enter_irqoff();
+
+ mds_user_clear_cpu_buffers();
}
#define SYSCALL_EXIT_WORK_FLAGS \
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index c022732e2cf9..912d509d34fc 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -317,6 +317,8 @@ DECLARE_STATIC_KEY_FALSE(switch_to_cond_stibp);
DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
+DECLARE_STATIC_KEY_FALSE(mds_user_clear);
+
#include <asm/segment.h>
/**
@@ -342,6 +344,17 @@ static inline void mds_clear_cpu_buffers(void)
asm volatile("verw %[ds]" : : [ds] "m" (ds) : "cc");
}
+/**
+ * mds_user_clear_cpu_buffers - Mitigation for MDS vulnerability
+ *
+ * Clear CPU buffers if the corresponding static key is enabled
+ */
+static inline void mds_user_clear_cpu_buffers(void)
+{
+ if (static_branch_likely(&mds_user_clear))
+ mds_clear_cpu_buffers();
+}
+
#endif /* __ASSEMBLY__ */
/*
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index e5258bd64200..2a69046cc38c 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -61,6 +61,9 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
/* Control unconditional IBPB in switch_mm() */
DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
+/* Control MDS CPU buffer clear before returning to user space */
+DEFINE_STATIC_KEY_FALSE(mds_user_clear);
+
void __init check_bugs(void)
{
identify_boot_cpu();
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index 18bc9b51ac9b..086cf1d1d71d 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -34,6 +34,7 @@
#include <asm/x86_init.h>
#include <asm/reboot.h>
#include <asm/cache.h>
+#include <asm/nospec-branch.h>
#define CREATE_TRACE_POINTS
#include <trace/events/nmi.h>
@@ -533,6 +534,9 @@ do_nmi(struct pt_regs *regs, long error_code)
write_cr2(this_cpu_read(nmi_cr2));
if (this_cpu_dec_return(nmi_state))
goto nmi_restart;
+
+ if (user_mode(regs))
+ mds_user_clear_cpu_buffers();
}
NOKPROBE_SYMBOL(do_nmi);
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index e6db475164ed..0a5efd764914 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -58,6 +58,7 @@
#include <asm/alternative.h>
#include <asm/fpu/xstate.h>
#include <asm/trace/mpx.h>
+#include <asm/nospec-branch.h>
#include <asm/mpx.h>
#include <asm/vm86.h>
#include <asm/umip.h>
@@ -387,6 +388,13 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
regs->ip = (unsigned long)general_protection;
regs->sp = (unsigned long)&gpregs->orig_ax;
+ /*
+ * This situation can be triggered by userspace via
+ * modify_ldt(2) and the return does not take the regular
+ * user space exit, so a CPU buffer clear is required when
+ * MDS mitigation is enabled.
+ */
+ mds_user_clear_cpu_buffers();
return;
}
#endif

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@ -0,0 +1,56 @@
From d04d9bffb07223cb687be8f5fbb059e6fa84b25a Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 27 Feb 2019 12:48:14 +0100
Subject: [PATCH 11/30] x86/kvm/vmx: Add MDS protection when L1D Flush is not
active
commit 650b68a0622f933444a6d66936abb3103029413b upstream
CPUs which are affected by L1TF and MDS mitigate MDS with the L1D Flush on
VMENTER when updated microcode is installed.
If a CPU is not affected by L1TF or if the L1D Flush is not in use, then
MDS mitigation needs to be invoked explicitly.
For these cases, follow the host mitigation state and invoke the MDS
mitigation before VMENTER.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
arch/x86/kernel/cpu/bugs.c | 1 +
arch/x86/kvm/vmx.c | 3 +++
2 files changed, 4 insertions(+)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 2a69046cc38c..c01468ccefc1 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -63,6 +63,7 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
/* Control MDS CPU buffer clear before returning to user space */
DEFINE_STATIC_KEY_FALSE(mds_user_clear);
+EXPORT_SYMBOL_GPL(mds_user_clear);
void __init check_bugs(void)
{
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 215339c7d161..e9bf477209dc 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -10765,8 +10765,11 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
evmcs_rsp = static_branch_unlikely(&enable_evmcs) ?
(unsigned long)&current_evmcs->host_rsp : 0;
+ /* L1D Flush includes CPU buffer clear to mitigate MDS */
if (static_branch_unlikely(&vmx_l1d_should_flush))
vmx_l1d_flush(vcpu);
+ else if (static_branch_unlikely(&mds_user_clear))
+ mds_clear_cpu_buffers();
asm(
/* Store host registers */

View File

@ -0,0 +1,223 @@
From e7505a450c34e89009ba48c459c08397ee3fc227 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 18 Feb 2019 23:04:01 +0100
Subject: [PATCH 12/30] x86/speculation/mds: Conditionally clear CPU buffers on
idle entry
commit 07f07f55a29cb705e221eda7894dd67ab81ef343 upstream
Add a static key which controls the invocation of the CPU buffer clear
mechanism on idle entry. This is independent of other MDS mitigations
because the idle entry invocation to mitigate the potential leakage due to
store buffer repartitioning is only necessary on SMT systems.
Add the actual invocations to the different halt/mwait variants which
covers all usage sites. mwaitx is not patched as it's not available on
Intel CPUs.
The buffer clear is only invoked before entering the C-State to prevent
that stale data from the idling CPU is spilled to the Hyper-Thread sibling
after the Store buffer got repartitioned and all entries are available to
the non idle sibling.
When coming out of idle the store buffer is partitioned again so each
sibling has half of it available. Now CPU which returned from idle could be
speculatively exposed to contents of the sibling, but the buffers are
flushed either on exit to user space or on VMENTER.
When later on conditional buffer clearing is implemented on top of this,
then there is no action required either because before returning to user
space the context switch will set the condition flag which causes a flush
on the return to user path.
Note, that the buffer clearing on idle is only sensible on CPUs which are
solely affected by MSBDS and not any other variant of MDS because the other
MDS variants cannot be mitigated when SMT is enabled, so the buffer
clearing on idle would be a window dressing exercise.
This intentionally does not handle the case in the acpi/processor_idle
driver which uses the legacy IO port interface for C-State transitions for
two reasons:
- The acpi/processor_idle driver was replaced by the intel_idle driver
almost a decade ago. Anything Nehalem upwards supports it and defaults
to that new driver.
- The legacy IO port interface is likely to be used on older and therefore
unaffected CPUs or on systems which do not receive microcode updates
anymore, so there is no point in adding that.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
Documentation/x86/mds.rst | 42 ++++++++++++++++++++++++++++
arch/x86/include/asm/irqflags.h | 4 +++
arch/x86/include/asm/mwait.h | 7 +++++
arch/x86/include/asm/nospec-branch.h | 12 ++++++++
arch/x86/kernel/cpu/bugs.c | 3 ++
5 files changed, 68 insertions(+)
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 54d935bf283b..87ce8ac9f36e 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -149,3 +149,45 @@ Mitigation points
This takes the paranoid exit path only when the INT1 breakpoint is in
kernel space. #DB on a user space address takes the regular exit path,
so no extra mitigation required.
+
+
+2. C-State transition
+^^^^^^^^^^^^^^^^^^^^^
+
+ When a CPU goes idle and enters a C-State the CPU buffers need to be
+ cleared on affected CPUs when SMT is active. This addresses the
+ repartitioning of the store buffer when one of the Hyper-Threads enters
+ a C-State.
+
+ When SMT is inactive, i.e. either the CPU does not support it or all
+ sibling threads are offline CPU buffer clearing is not required.
+
+ The idle clearing is enabled on CPUs which are only affected by MSBDS
+ and not by any other MDS variant. The other MDS variants cannot be
+ protected against cross Hyper-Thread attacks because the Fill Buffer and
+ the Load Ports are shared. So on CPUs affected by other variants, the
+ idle clearing would be a window dressing exercise and is therefore not
+ activated.
+
+ The invocation is controlled by the static key mds_idle_clear which is
+ switched depending on the chosen mitigation mode and the SMT state of
+ the system.
+
+ The buffer clear is only invoked before entering the C-State to prevent
+ that stale data from the idling CPU from spilling to the Hyper-Thread
+ sibling after the store buffer got repartitioned and all entries are
+ available to the non idle sibling.
+
+ When coming out of idle the store buffer is partitioned again so each
+ sibling has half of it available. The back from idle CPU could be then
+ speculatively exposed to contents of the sibling. The buffers are
+ flushed either on exit to user space or on VMENTER so malicious code
+ in user space or the guest cannot speculatively access them.
+
+ The mitigation is hooked into all variants of halt()/mwait(), but does
+ not cover the legacy ACPI IO-Port mechanism because the ACPI idle driver
+ has been superseded by the intel_idle driver around 2010 and is
+ preferred on all affected CPUs which are expected to gain the MD_CLEAR
+ functionality in microcode. Aside of that the IO-Port mechanism is a
+ legacy interface which is only used on older systems which are either
+ not affected or do not receive microcode updates anymore.
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 15450a675031..c99c66b41e53 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -6,6 +6,8 @@
#ifndef __ASSEMBLY__
+#include <asm/nospec-branch.h>
+
/* Provide __cpuidle; we can't safely include <linux/cpu.h> */
#define __cpuidle __attribute__((__section__(".cpuidle.text")))
@@ -54,11 +56,13 @@ static inline void native_irq_enable(void)
static inline __cpuidle void native_safe_halt(void)
{
+ mds_idle_clear_cpu_buffers();
asm volatile("sti; hlt": : :"memory");
}
static inline __cpuidle void native_halt(void)
{
+ mds_idle_clear_cpu_buffers();
asm volatile("hlt": : :"memory");
}
diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h
index 39a2fb29378a..eb0f80ce8524 100644
--- a/arch/x86/include/asm/mwait.h
+++ b/arch/x86/include/asm/mwait.h
@@ -6,6 +6,7 @@
#include <linux/sched/idle.h>
#include <asm/cpufeature.h>
+#include <asm/nospec-branch.h>
#define MWAIT_SUBSTATE_MASK 0xf
#define MWAIT_CSTATE_MASK 0xf
@@ -40,6 +41,8 @@ static inline void __monitorx(const void *eax, unsigned long ecx,
static inline void __mwait(unsigned long eax, unsigned long ecx)
{
+ mds_idle_clear_cpu_buffers();
+
/* "mwait %eax, %ecx;" */
asm volatile(".byte 0x0f, 0x01, 0xc9;"
:: "a" (eax), "c" (ecx));
@@ -74,6 +77,8 @@ static inline void __mwait(unsigned long eax, unsigned long ecx)
static inline void __mwaitx(unsigned long eax, unsigned long ebx,
unsigned long ecx)
{
+ /* No MDS buffer clear as this is AMD/HYGON only */
+
/* "mwaitx %eax, %ebx, %ecx;" */
asm volatile(".byte 0x0f, 0x01, 0xfb;"
:: "a" (eax), "b" (ebx), "c" (ecx));
@@ -81,6 +86,8 @@ static inline void __mwaitx(unsigned long eax, unsigned long ebx,
static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
{
+ mds_idle_clear_cpu_buffers();
+
trace_hardirqs_on();
/* "mwait %eax, %ecx;" */
asm volatile("sti; .byte 0x0f, 0x01, 0xc9;"
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 912d509d34fc..599c273f5d00 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -318,6 +318,7 @@ DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
DECLARE_STATIC_KEY_FALSE(mds_user_clear);
+DECLARE_STATIC_KEY_FALSE(mds_idle_clear);
#include <asm/segment.h>
@@ -355,6 +356,17 @@ static inline void mds_user_clear_cpu_buffers(void)
mds_clear_cpu_buffers();
}
+/**
+ * mds_idle_clear_cpu_buffers - Mitigation for MDS vulnerability
+ *
+ * Clear CPU buffers if the corresponding static key is enabled
+ */
+static inline void mds_idle_clear_cpu_buffers(void)
+{
+ if (static_branch_likely(&mds_idle_clear))
+ mds_clear_cpu_buffers();
+}
+
#endif /* __ASSEMBLY__ */
/*
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index c01468ccefc1..428fe6590360 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -64,6 +64,9 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
/* Control MDS CPU buffer clear before returning to user space */
DEFINE_STATIC_KEY_FALSE(mds_user_clear);
EXPORT_SYMBOL_GPL(mds_user_clear);
+/* Control MDS CPU buffer clear before idling (halt, mwait) */
+DEFINE_STATIC_KEY_FALSE(mds_idle_clear);
+EXPORT_SYMBOL_GPL(mds_idle_clear);
void __init check_bugs(void)
{

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@ -0,0 +1,191 @@
From 892ec2b2472857d93fb2b3d125a13d9df4400ce0 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 18 Feb 2019 22:04:08 +0100
Subject: [PATCH 13/30] x86/speculation/mds: Add mitigation control for MDS
commit bc1241700acd82ec69fde98c5763ce51086269f8 upstream
Now that the mitigations are in place, add a command line parameter to
control the mitigation, a mitigation selector function and a SMT update
mechanism.
This is the minimal straight forward initial implementation which just
provides an always on/off mode. The command line parameter is:
mds=[full|off]
This is consistent with the existing mitigations for other speculative
hardware vulnerabilities.
The idle invocation is dynamically updated according to the SMT state of
the system similar to the dynamic update of the STIBP mitigation. The idle
mitigation is limited to CPUs which are only affected by MSBDS and not any
other variant, because the other variants cannot be mitigated on SMT
enabled systems.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
.../admin-guide/kernel-parameters.txt | 22 ++++++
arch/x86/include/asm/processor.h | 5 ++
arch/x86/kernel/cpu/bugs.c | 70 +++++++++++++++++++
3 files changed, 97 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 8b6567f7cb9b..a0ab4521d7c5 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2319,6 +2319,28 @@
Format: <first>,<last>
Specifies range of consoles to be captured by the MDA.
+ mds= [X86,INTEL]
+ Control mitigation for the Micro-architectural Data
+ Sampling (MDS) vulnerability.
+
+ Certain CPUs are vulnerable to an exploit against CPU
+ internal buffers which can forward information to a
+ disclosure gadget under certain conditions.
+
+ In vulnerable processors, the speculatively
+ forwarded data can be used in a cache side channel
+ attack, to access data to which the attacker does
+ not have direct access.
+
+ This parameter controls the MDS mitigation. The
+ options are:
+
+ full - Enable MDS mitigation on vulnerable CPUs
+ off - Unconditionally disable MDS mitigation
+
+ Not specifying this option is equivalent to
+ mds=full.
+
mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
Amount of memory to be used when the kernel is not able
to see the whole system memory or for test.
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index d53c54b842da..5e9f953face0 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -997,4 +997,9 @@ enum l1tf_mitigations {
extern enum l1tf_mitigations l1tf_mitigation;
+enum mds_mitigations {
+ MDS_MITIGATION_OFF,
+ MDS_MITIGATION_FULL,
+};
+
#endif /* _ASM_X86_PROCESSOR_H */
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 428fe6590360..413a672f03a3 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -35,6 +35,7 @@
static void __init spectre_v2_select_mitigation(void);
static void __init ssb_select_mitigation(void);
static void __init l1tf_select_mitigation(void);
+static void __init mds_select_mitigation(void);
/* The base value of the SPEC_CTRL MSR that always has to be preserved. */
u64 x86_spec_ctrl_base;
@@ -106,6 +107,8 @@ void __init check_bugs(void)
l1tf_select_mitigation();
+ mds_select_mitigation();
+
#ifdef CONFIG_X86_32
/*
* Check whether we are able to run this kernel safely on SMP.
@@ -211,6 +214,50 @@ static void x86_amd_ssb_disable(void)
wrmsrl(MSR_AMD64_LS_CFG, msrval);
}
+#undef pr_fmt
+#define pr_fmt(fmt) "MDS: " fmt
+
+/* Default mitigation for L1TF-affected CPUs */
+static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL;
+
+static const char * const mds_strings[] = {
+ [MDS_MITIGATION_OFF] = "Vulnerable",
+ [MDS_MITIGATION_FULL] = "Mitigation: Clear CPU buffers"
+};
+
+static void __init mds_select_mitigation(void)
+{
+ if (!boot_cpu_has_bug(X86_BUG_MDS)) {
+ mds_mitigation = MDS_MITIGATION_OFF;
+ return;
+ }
+
+ if (mds_mitigation == MDS_MITIGATION_FULL) {
+ if (boot_cpu_has(X86_FEATURE_MD_CLEAR))
+ static_branch_enable(&mds_user_clear);
+ else
+ mds_mitigation = MDS_MITIGATION_OFF;
+ }
+ pr_info("%s\n", mds_strings[mds_mitigation]);
+}
+
+static int __init mds_cmdline(char *str)
+{
+ if (!boot_cpu_has_bug(X86_BUG_MDS))
+ return 0;
+
+ if (!str)
+ return -EINVAL;
+
+ if (!strcmp(str, "off"))
+ mds_mitigation = MDS_MITIGATION_OFF;
+ else if (!strcmp(str, "full"))
+ mds_mitigation = MDS_MITIGATION_FULL;
+
+ return 0;
+}
+early_param("mds", mds_cmdline);
+
#undef pr_fmt
#define pr_fmt(fmt) "Spectre V2 : " fmt
@@ -603,6 +650,26 @@ static void update_indir_branch_cond(void)
static_branch_disable(&switch_to_cond_stibp);
}
+/* Update the static key controlling the MDS CPU buffer clear in idle */
+static void update_mds_branch_idle(void)
+{
+ /*
+ * Enable the idle clearing if SMT is active on CPUs which are
+ * affected only by MSBDS and not any other MDS variant.
+ *
+ * The other variants cannot be mitigated when SMT is enabled, so
+ * clearing the buffers on idle just to prevent the Store Buffer
+ * repartitioning leak would be a window dressing exercise.
+ */
+ if (!boot_cpu_has_bug(X86_BUG_MSBDS_ONLY))
+ return;
+
+ if (sched_smt_active())
+ static_branch_enable(&mds_idle_clear);
+ else
+ static_branch_disable(&mds_idle_clear);
+}
+
void arch_smt_update(void)
{
/* Enhanced IBRS implies STIBP. No update required. */
@@ -623,6 +690,9 @@ void arch_smt_update(void)
break;
}
+ if (mds_mitigation == MDS_MITIGATION_FULL)
+ update_mds_branch_idle();
+
mutex_unlock(&spec_ctrl_mutex);
}

View File

@ -0,0 +1,127 @@
From dc5e8f6e2934df2c4a459c932d123843d0c2375d Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Mon, 18 Feb 2019 22:51:43 +0100
Subject: [PATCH 14/30] x86/speculation/mds: Add sysfs reporting for MDS
commit 8a4b06d391b0a42a373808979b5028f5c84d9c6a upstream
Add the sysfs reporting file for MDS. It exposes the vulnerability and
mitigation state similar to the existing files for the other speculative
hardware vulnerabilities.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
.../ABI/testing/sysfs-devices-system-cpu | 1 +
arch/x86/kernel/cpu/bugs.c | 25 +++++++++++++++++++
drivers/base/cpu.c | 8 ++++++
include/linux/cpu.h | 2 ++
4 files changed, 36 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 73318225a368..02b7bb711214 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -477,6 +477,7 @@ What: /sys/devices/system/cpu/vulnerabilities
/sys/devices/system/cpu/vulnerabilities/spectre_v2
/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
/sys/devices/system/cpu/vulnerabilities/l1tf
+ /sys/devices/system/cpu/vulnerabilities/mds
Date: January 2018
Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org>
Description: Information about CPU vulnerabilities
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 413a672f03a3..50b7d2a980e8 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1154,6 +1154,22 @@ static ssize_t l1tf_show_state(char *buf)
}
#endif
+static ssize_t mds_show_state(char *buf)
+{
+ if (!hypervisor_is_type(X86_HYPER_NATIVE)) {
+ return sprintf(buf, "%s; SMT Host state unknown\n",
+ mds_strings[mds_mitigation]);
+ }
+
+ if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) {
+ return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+ sched_smt_active() ? "mitigated" : "disabled");
+ }
+
+ return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+ sched_smt_active() ? "vulnerable" : "disabled");
+}
+
static char *stibp_state(void)
{
if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
@@ -1218,6 +1234,10 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
if (boot_cpu_has(X86_FEATURE_L1TF_PTEINV))
return l1tf_show_state(buf);
break;
+
+ case X86_BUG_MDS:
+ return mds_show_state(buf);
+
default:
break;
}
@@ -1249,4 +1269,9 @@ ssize_t cpu_show_l1tf(struct device *dev, struct device_attribute *attr, char *b
{
return cpu_show_common(dev, attr, buf, X86_BUG_L1TF);
}
+
+ssize_t cpu_show_mds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_MDS);
+}
#endif
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index eb9443d5bae1..2fd6ca1021c2 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -546,11 +546,18 @@ ssize_t __weak cpu_show_l1tf(struct device *dev,
return sprintf(buf, "Not affected\n");
}
+ssize_t __weak cpu_show_mds(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "Not affected\n");
+}
+
static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
static DEVICE_ATTR(spec_store_bypass, 0444, cpu_show_spec_store_bypass, NULL);
static DEVICE_ATTR(l1tf, 0444, cpu_show_l1tf, NULL);
+static DEVICE_ATTR(mds, 0444, cpu_show_mds, NULL);
static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_meltdown.attr,
@@ -558,6 +565,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_spectre_v2.attr,
&dev_attr_spec_store_bypass.attr,
&dev_attr_l1tf.attr,
+ &dev_attr_mds.attr,
NULL
};
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 5041357d0297..3c87ad888ed3 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -57,6 +57,8 @@ extern ssize_t cpu_show_spec_store_bypass(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_l1tf(struct device *dev,
struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_mds(struct device *dev,
+ struct device_attribute *attr, char *buf);
extern __printf(4, 5)
struct device *cpu_device_create(struct device *parent, void *drvdata,

View File

@ -0,0 +1,129 @@
From 66260821438fb5c3e8b4b662c1ebd6ba0b077c09 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 20 Feb 2019 09:40:40 +0100
Subject: [PATCH 15/30] x86/speculation/mds: Add mitigation mode VMWERV
commit 22dd8365088b6403630b82423cf906491859b65e upstream
In virtualized environments it can happen that the host has the microcode
update which utilizes the VERW instruction to clear CPU buffers, but the
hypervisor is not yet updated to expose the X86_FEATURE_MD_CLEAR CPUID bit
to guests.
Introduce an internal mitigation mode VMWERV which enables the invocation
of the CPU buffer clearing even if X86_FEATURE_MD_CLEAR is not set. If the
system has no updated microcode this results in a pointless execution of
the VERW instruction wasting a few CPU cycles. If the microcode is updated,
but not exposed to a guest then the CPU buffers will be cleared.
That said: Virtual Machines Will Eventually Receive Vaccine
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
---
Documentation/x86/mds.rst | 27 +++++++++++++++++++++++++++
arch/x86/include/asm/processor.h | 1 +
arch/x86/kernel/cpu/bugs.c | 18 ++++++++++++------
3 files changed, 40 insertions(+), 6 deletions(-)
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 87ce8ac9f36e..3d6f943f1afb 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -93,11 +93,38 @@ enters a C-state.
The mitigation is invoked on kernel/userspace, hypervisor/guest and C-state
(idle) transitions.
+As a special quirk to address virtualization scenarios where the host has
+the microcode updated, but the hypervisor does not (yet) expose the
+MD_CLEAR CPUID bit to guests, the kernel issues the VERW instruction in the
+hope that it might actually clear the buffers. The state is reflected
+accordingly.
+
According to current knowledge additional mitigations inside the kernel
itself are not required because the necessary gadgets to expose the leaked
data cannot be controlled in a way which allows exploitation from malicious
user space or VM guests.
+Kernel internal mitigation modes
+--------------------------------
+
+ ======= ============================================================
+ off Mitigation is disabled. Either the CPU is not affected or
+ mds=off is supplied on the kernel command line
+
+ full Mitigation is eanbled. CPU is affected and MD_CLEAR is
+ advertised in CPUID.
+
+ vmwerv Mitigation is enabled. CPU is affected and MD_CLEAR is not
+ advertised in CPUID. That is mainly for virtualization
+ scenarios where the host has the updated microcode but the
+ hypervisor does not expose MD_CLEAR in CPUID. It's a best
+ effort approach without guarantee.
+ ======= ============================================================
+
+If the CPU is affected and mds=off is not supplied on the kernel command
+line then the kernel selects the appropriate mitigation mode depending on
+the availability of the MD_CLEAR CPUID bit.
+
Mitigation points
-----------------
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 5e9f953face0..b54f25697beb 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -1000,6 +1000,7 @@ extern enum l1tf_mitigations l1tf_mitigation;
enum mds_mitigations {
MDS_MITIGATION_OFF,
MDS_MITIGATION_FULL,
+ MDS_MITIGATION_VMWERV,
};
#endif /* _ASM_X86_PROCESSOR_H */
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 50b7d2a980e8..053d71a3b9cc 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -222,7 +222,8 @@ static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL
static const char * const mds_strings[] = {
[MDS_MITIGATION_OFF] = "Vulnerable",
- [MDS_MITIGATION_FULL] = "Mitigation: Clear CPU buffers"
+ [MDS_MITIGATION_FULL] = "Mitigation: Clear CPU buffers",
+ [MDS_MITIGATION_VMWERV] = "Vulnerable: Clear CPU buffers attempted, no microcode",
};
static void __init mds_select_mitigation(void)
@@ -233,10 +234,9 @@ static void __init mds_select_mitigation(void)
}
if (mds_mitigation == MDS_MITIGATION_FULL) {
- if (boot_cpu_has(X86_FEATURE_MD_CLEAR))
- static_branch_enable(&mds_user_clear);
- else
- mds_mitigation = MDS_MITIGATION_OFF;
+ if (!boot_cpu_has(X86_FEATURE_MD_CLEAR))
+ mds_mitigation = MDS_MITIGATION_VMWERV;
+ static_branch_enable(&mds_user_clear);
}
pr_info("%s\n", mds_strings[mds_mitigation]);
}
@@ -690,8 +690,14 @@ void arch_smt_update(void)
break;
}
- if (mds_mitigation == MDS_MITIGATION_FULL)
+ switch (mds_mitigation) {
+ case MDS_MITIGATION_FULL:
+ case MDS_MITIGATION_VMWERV:
update_mds_branch_idle();
+ break;
+ case MDS_MITIGATION_OFF:
+ break;
+ }
mutex_unlock(&spec_ctrl_mutex);
}

View File

@ -0,0 +1,123 @@
From 83852a8b0064f1360980a690792c3f438aec06b9 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Tue, 19 Feb 2019 11:10:49 +0100
Subject: [PATCH 16/30] Documentation: Move L1TF to separate directory
commit 65fd4cb65b2dad97feb8330b6690445910b56d6a upstream
Move L!TF to a separate directory so the MDS stuff can be added at the
side. Otherwise the all hardware vulnerabilites have their own top level
entry. Should have done that right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jon Masters <jcm@redhat.com>
---
Documentation/ABI/testing/sysfs-devices-system-cpu | 2 +-
Documentation/admin-guide/hw-vuln/index.rst | 12 ++++++++++++
Documentation/admin-guide/{ => hw-vuln}/l1tf.rst | 0
Documentation/admin-guide/index.rst | 6 ++----
Documentation/admin-guide/kernel-parameters.txt | 2 +-
arch/x86/kernel/cpu/bugs.c | 2 +-
arch/x86/kvm/vmx.c | 4 ++--
7 files changed, 19 insertions(+), 9 deletions(-)
create mode 100644 Documentation/admin-guide/hw-vuln/index.rst
rename Documentation/admin-guide/{ => hw-vuln}/l1tf.rst (100%)
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 02b7bb711214..f397c2382171 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -491,7 +491,7 @@ Description: Information about CPU vulnerabilities
"Mitigation: $M" CPU is affected and mitigation $M is in effect
Details about the l1tf file can be found in
- Documentation/admin-guide/l1tf.rst
+ Documentation/admin-guide/hw-vuln/l1tf.rst
What: /sys/devices/system/cpu/smt
/sys/devices/system/cpu/smt/active
diff --git a/Documentation/admin-guide/hw-vuln/index.rst b/Documentation/admin-guide/hw-vuln/index.rst
new file mode 100644
index 000000000000..8ce2009f1981
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/index.rst
@@ -0,0 +1,12 @@
+========================
+Hardware vulnerabilities
+========================
+
+This section describes CPU vulnerabilities and provides an overview of the
+possible mitigations along with guidance for selecting mitigations if they
+are configurable at compile, boot or run time.
+
+.. toctree::
+ :maxdepth: 1
+
+ l1tf
diff --git a/Documentation/admin-guide/l1tf.rst b/Documentation/admin-guide/hw-vuln/l1tf.rst
similarity index 100%
rename from Documentation/admin-guide/l1tf.rst
rename to Documentation/admin-guide/hw-vuln/l1tf.rst
diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst
index 0873685bab0f..89abc5057349 100644
--- a/Documentation/admin-guide/index.rst
+++ b/Documentation/admin-guide/index.rst
@@ -17,14 +17,12 @@ etc.
kernel-parameters
devices
-This section describes CPU vulnerabilities and provides an overview of the
-possible mitigations along with guidance for selecting mitigations if they
-are configurable at compile, boot or run time.
+This section describes CPU vulnerabilities and their mitigations.
.. toctree::
:maxdepth: 1
- l1tf
+ hw-vuln/index
Here is a set of documents aimed at users who are trying to track down
problems and bugs in particular.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a0ab4521d7c5..b2c9e47c4167 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2079,7 +2079,7 @@
Default is 'flush'.
- For details see: Documentation/admin-guide/l1tf.rst
+ For details see: Documentation/admin-guide/hw-vuln/l1tf.rst
l2cr= [PPC]
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 053d71a3b9cc..a7e54a91abc4 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1089,7 +1089,7 @@ static void __init l1tf_select_mitigation(void)
pr_info("You may make it effective by booting the kernel with mem=%llu parameter.\n",
half_pa);
pr_info("However, doing so will make a part of your RAM unusable.\n");
- pr_info("Reading https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html might help you decide.\n");
+ pr_info("Reading https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html might help you decide.\n");
return;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e9bf477209dc..73d6d585dd66 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -11130,8 +11130,8 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
return ERR_PTR(err);
}
-#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html for details.\n"
-#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html for details.\n"
+#define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
+#define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
static int vmx_vm_init(struct kvm *kvm)
{

View File

@ -0,0 +1,381 @@
From 4fb7f5dc689d79884f4e6e33f5d2704f44edd42a Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Tue, 19 Feb 2019 00:02:31 +0100
Subject: [PATCH 17/30] Documentation: Add MDS vulnerability documentation
commit 5999bbe7a6ea3c62029532ec84dc06003a1fa258 upstream
Add the initial MDS vulnerability documentation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jon Masters <jcm@redhat.com>
---
.../ABI/testing/sysfs-devices-system-cpu | 3 +-
Documentation/admin-guide/hw-vuln/index.rst | 1 +
Documentation/admin-guide/hw-vuln/l1tf.rst | 1 +
Documentation/admin-guide/hw-vuln/mds.rst | 307 ++++++++++++++++++
.../admin-guide/kernel-parameters.txt | 2 +
5 files changed, 312 insertions(+), 2 deletions(-)
create mode 100644 Documentation/admin-guide/hw-vuln/mds.rst
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index f397c2382171..8718d4ad227b 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -490,8 +490,7 @@ Description: Information about CPU vulnerabilities
"Vulnerable" CPU is affected and no mitigation in effect
"Mitigation: $M" CPU is affected and mitigation $M is in effect
- Details about the l1tf file can be found in
- Documentation/admin-guide/hw-vuln/l1tf.rst
+ See also: Documentation/admin-guide/hw-vuln/index.rst
What: /sys/devices/system/cpu/smt
/sys/devices/system/cpu/smt/active
diff --git a/Documentation/admin-guide/hw-vuln/index.rst b/Documentation/admin-guide/hw-vuln/index.rst
index 8ce2009f1981..ffc064c1ec68 100644
--- a/Documentation/admin-guide/hw-vuln/index.rst
+++ b/Documentation/admin-guide/hw-vuln/index.rst
@@ -10,3 +10,4 @@ are configurable at compile, boot or run time.
:maxdepth: 1
l1tf
+ mds
diff --git a/Documentation/admin-guide/hw-vuln/l1tf.rst b/Documentation/admin-guide/hw-vuln/l1tf.rst
index 9af977384168..31653a9f0e1b 100644
--- a/Documentation/admin-guide/hw-vuln/l1tf.rst
+++ b/Documentation/admin-guide/hw-vuln/l1tf.rst
@@ -445,6 +445,7 @@ The default is 'cond'. If 'l1tf=full,force' is given on the kernel command
line, then 'always' is enforced and the kvm-intel.vmentry_l1d_flush
module parameter is ignored and writes to the sysfs file are rejected.
+.. _mitigation_selection:
Mitigation selection guide
--------------------------
diff --git a/Documentation/admin-guide/hw-vuln/mds.rst b/Documentation/admin-guide/hw-vuln/mds.rst
new file mode 100644
index 000000000000..1de29d28903d
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/mds.rst
@@ -0,0 +1,307 @@
+MDS - Microarchitectural Data Sampling
+======================================
+
+Microarchitectural Data Sampling is a hardware vulnerability which allows
+unprivileged speculative access to data which is available in various CPU
+internal buffers.
+
+Affected processors
+-------------------
+
+This vulnerability affects a wide range of Intel processors. The
+vulnerability is not present on:
+
+ - Processors from AMD, Centaur and other non Intel vendors
+
+ - Older processor models, where the CPU family is < 6
+
+ - Some Atoms (Bonnell, Saltwell, Goldmont, GoldmontPlus)
+
+ - Intel processors which have the ARCH_CAP_MDS_NO bit set in the
+ IA32_ARCH_CAPABILITIES MSR.
+
+Whether a processor is affected or not can be read out from the MDS
+vulnerability file in sysfs. See :ref:`mds_sys_info`.
+
+Not all processors are affected by all variants of MDS, but the mitigation
+is identical for all of them so the kernel treats them as a single
+vulnerability.
+
+Related CVEs
+------------
+
+The following CVE entries are related to the MDS vulnerability:
+
+ ============== ===== ==============================================
+ CVE-2018-12126 MSBDS Microarchitectural Store Buffer Data Sampling
+ CVE-2018-12130 MFBDS Microarchitectural Fill Buffer Data Sampling
+ CVE-2018-12127 MLPDS Microarchitectural Load Port Data Sampling
+ ============== ===== ==============================================
+
+Problem
+-------
+
+When performing store, load, L1 refill operations, processors write data
+into temporary microarchitectural structures (buffers). The data in the
+buffer can be forwarded to load operations as an optimization.
+
+Under certain conditions, usually a fault/assist caused by a load
+operation, data unrelated to the load memory address can be speculatively
+forwarded from the buffers. Because the load operation causes a fault or
+assist and its result will be discarded, the forwarded data will not cause
+incorrect program execution or state changes. But a malicious operation
+may be able to forward this speculative data to a disclosure gadget which
+allows in turn to infer the value via a cache side channel attack.
+
+Because the buffers are potentially shared between Hyper-Threads cross
+Hyper-Thread attacks are possible.
+
+Deeper technical information is available in the MDS specific x86
+architecture section: :ref:`Documentation/x86/mds.rst <mds>`.
+
+
+Attack scenarios
+----------------
+
+Attacks against the MDS vulnerabilities can be mounted from malicious non
+priviledged user space applications running on hosts or guest. Malicious
+guest OSes can obviously mount attacks as well.
+
+Contrary to other speculation based vulnerabilities the MDS vulnerability
+does not allow the attacker to control the memory target address. As a
+consequence the attacks are purely sampling based, but as demonstrated with
+the TLBleed attack samples can be postprocessed successfully.
+
+Web-Browsers
+^^^^^^^^^^^^
+
+ It's unclear whether attacks through Web-Browsers are possible at
+ all. The exploitation through Java-Script is considered very unlikely,
+ but other widely used web technologies like Webassembly could possibly be
+ abused.
+
+
+.. _mds_sys_info:
+
+MDS system information
+-----------------------
+
+The Linux kernel provides a sysfs interface to enumerate the current MDS
+status of the system: whether the system is vulnerable, and which
+mitigations are active. The relevant sysfs file is:
+
+/sys/devices/system/cpu/vulnerabilities/mds
+
+The possible values in this file are:
+
+ ========================================= =================================
+ 'Not affected' The processor is not vulnerable
+
+ 'Vulnerable' The processor is vulnerable,
+ but no mitigation enabled
+
+ 'Vulnerable: Clear CPU buffers attempted' The processor is vulnerable but
+ microcode is not updated.
+ The mitigation is enabled on a
+ best effort basis.
+ See :ref:`vmwerv`
+
+ 'Mitigation: CPU buffer clear' The processor is vulnerable and the
+ CPU buffer clearing mitigation is
+ enabled.
+ ========================================= =================================
+
+If the processor is vulnerable then the following information is appended
+to the above information:
+
+ ======================== ============================================
+ 'SMT vulnerable' SMT is enabled
+ 'SMT mitigated' SMT is enabled and mitigated
+ 'SMT disabled' SMT is disabled
+ 'SMT Host state unknown' Kernel runs in a VM, Host SMT state unknown
+ ======================== ============================================
+
+.. _vmwerv:
+
+Best effort mitigation mode
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ If the processor is vulnerable, but the availability of the microcode based
+ mitigation mechanism is not advertised via CPUID the kernel selects a best
+ effort mitigation mode. This mode invokes the mitigation instructions
+ without a guarantee that they clear the CPU buffers.
+
+ This is done to address virtualization scenarios where the host has the
+ microcode update applied, but the hypervisor is not yet updated to expose
+ the CPUID to the guest. If the host has updated microcode the protection
+ takes effect otherwise a few cpu cycles are wasted pointlessly.
+
+ The state in the mds sysfs file reflects this situation accordingly.
+
+
+Mitigation mechanism
+-------------------------
+
+The kernel detects the affected CPUs and the presence of the microcode
+which is required.
+
+If a CPU is affected and the microcode is available, then the kernel
+enables the mitigation by default. The mitigation can be controlled at boot
+time via a kernel command line option. See
+:ref:`mds_mitigation_control_command_line`.
+
+.. _cpu_buffer_clear:
+
+CPU buffer clearing
+^^^^^^^^^^^^^^^^^^^
+
+ The mitigation for MDS clears the affected CPU buffers on return to user
+ space and when entering a guest.
+
+ If SMT is enabled it also clears the buffers on idle entry when the CPU
+ is only affected by MSBDS and not any other MDS variant, because the
+ other variants cannot be protected against cross Hyper-Thread attacks.
+
+ For CPUs which are only affected by MSBDS the user space, guest and idle
+ transition mitigations are sufficient and SMT is not affected.
+
+.. _virt_mechanism:
+
+Virtualization mitigation
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ The protection for host to guest transition depends on the L1TF
+ vulnerability of the CPU:
+
+ - CPU is affected by L1TF:
+
+ If the L1D flush mitigation is enabled and up to date microcode is
+ available, the L1D flush mitigation is automatically protecting the
+ guest transition.
+
+ If the L1D flush mitigation is disabled then the MDS mitigation is
+ invoked explicit when the host MDS mitigation is enabled.
+
+ For details on L1TF and virtualization see:
+ :ref:`Documentation/admin-guide/hw-vuln//l1tf.rst <mitigation_control_kvm>`.
+
+ - CPU is not affected by L1TF:
+
+ CPU buffers are flushed before entering the guest when the host MDS
+ mitigation is enabled.
+
+ The resulting MDS protection matrix for the host to guest transition:
+
+ ============ ===== ============= ============ =================
+ L1TF MDS VMX-L1FLUSH Host MDS MDS-State
+
+ Don't care No Don't care N/A Not affected
+
+ Yes Yes Disabled Off Vulnerable
+
+ Yes Yes Disabled Full Mitigated
+
+ Yes Yes Enabled Don't care Mitigated
+
+ No Yes N/A Off Vulnerable
+
+ No Yes N/A Full Mitigated
+ ============ ===== ============= ============ =================
+
+ This only covers the host to guest transition, i.e. prevents leakage from
+ host to guest, but does not protect the guest internally. Guests need to
+ have their own protections.
+
+.. _xeon_phi:
+
+XEON PHI specific considerations
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ The XEON PHI processor family is affected by MSBDS which can be exploited
+ cross Hyper-Threads when entering idle states. Some XEON PHI variants allow
+ to use MWAIT in user space (Ring 3) which opens an potential attack vector
+ for malicious user space. The exposure can be disabled on the kernel
+ command line with the 'ring3mwait=disable' command line option.
+
+ XEON PHI is not affected by the other MDS variants and MSBDS is mitigated
+ before the CPU enters a idle state. As XEON PHI is not affected by L1TF
+ either disabling SMT is not required for full protection.
+
+.. _mds_smt_control:
+
+SMT control
+^^^^^^^^^^^
+
+ All MDS variants except MSBDS can be attacked cross Hyper-Threads. That
+ means on CPUs which are affected by MFBDS or MLPDS it is necessary to
+ disable SMT for full protection. These are most of the affected CPUs; the
+ exception is XEON PHI, see :ref:`xeon_phi`.
+
+ Disabling SMT can have a significant performance impact, but the impact
+ depends on the type of workloads.
+
+ See the relevant chapter in the L1TF mitigation documentation for details:
+ :ref:`Documentation/admin-guide/hw-vuln/l1tf.rst <smt_control>`.
+
+
+.. _mds_mitigation_control_command_line:
+
+Mitigation control on the kernel command line
+---------------------------------------------
+
+The kernel command line allows to control the MDS mitigations at boot
+time with the option "mds=". The valid arguments for this option are:
+
+ ============ =============================================================
+ full If the CPU is vulnerable, enable all available mitigations
+ for the MDS vulnerability, CPU buffer clearing on exit to
+ userspace and when entering a VM. Idle transitions are
+ protected as well if SMT is enabled.
+
+ It does not automatically disable SMT.
+
+ off Disables MDS mitigations completely.
+
+ ============ =============================================================
+
+Not specifying this option is equivalent to "mds=full".
+
+
+Mitigation selection guide
+--------------------------
+
+1. Trusted userspace
+^^^^^^^^^^^^^^^^^^^^
+
+ If all userspace applications are from a trusted source and do not
+ execute untrusted code which is supplied externally, then the mitigation
+ can be disabled.
+
+
+2. Virtualization with trusted guests
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ The same considerations as above versus trusted user space apply.
+
+3. Virtualization with untrusted guests
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+ The protection depends on the state of the L1TF mitigations.
+ See :ref:`virt_mechanism`.
+
+ If the MDS mitigation is enabled and SMT is disabled, guest to host and
+ guest to guest attacks are prevented.
+
+.. _mds_default_mitigations:
+
+Default mitigations
+-------------------
+
+ The kernel default mitigations for vulnerable processors are:
+
+ - Enable CPU buffer clearing
+
+ The kernel does not by default enforce the disabling of SMT, which leaves
+ SMT systems vulnerable when running untrusted code. The same rationale as
+ for L1TF applies.
+ See :ref:`Documentation/admin-guide/hw-vuln//l1tf.rst <default_mitigations>`.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b2c9e47c4167..290f0946f2ef 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2341,6 +2341,8 @@
Not specifying this option is equivalent to
mds=full.
+ For details see: Documentation/admin-guide/hw-vuln/mds.rst
+
mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
Amount of memory to be used when the kernel is not able
to see the whole system memory or for test.

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@ -0,0 +1,88 @@
From 71cd118bd3491d54b45c8185bb0d8c3a2466424f Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 2 Apr 2019 09:59:33 -0500
Subject: [PATCH 18/30] x86/speculation/mds: Add mds=full,nosmt cmdline option
commit d71eb0ce109a124b0fa714832823b9452f2762cf upstream
Add the mds=full,nosmt cmdline option. This is like mds=full, but with
SMT disabled if the CPU is vulnerable.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
---
Documentation/admin-guide/hw-vuln/mds.rst | 3 +++
Documentation/admin-guide/kernel-parameters.txt | 6 ++++--
arch/x86/kernel/cpu/bugs.c | 10 ++++++++++
3 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/Documentation/admin-guide/hw-vuln/mds.rst b/Documentation/admin-guide/hw-vuln/mds.rst
index 1de29d28903d..244ab47d1fb3 100644
--- a/Documentation/admin-guide/hw-vuln/mds.rst
+++ b/Documentation/admin-guide/hw-vuln/mds.rst
@@ -260,6 +260,9 @@ The kernel command line allows to control the MDS mitigations at boot
It does not automatically disable SMT.
+ full,nosmt The same as mds=full, with SMT disabled on vulnerable
+ CPUs. This is the complete mitigation.
+
off Disables MDS mitigations completely.
============ =============================================================
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 290f0946f2ef..df8d10668b11 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2335,8 +2335,10 @@
This parameter controls the MDS mitigation. The
options are:
- full - Enable MDS mitigation on vulnerable CPUs
- off - Unconditionally disable MDS mitigation
+ full - Enable MDS mitigation on vulnerable CPUs
+ full,nosmt - Enable MDS mitigation and disable
+ SMT on vulnerable CPUs
+ off - Unconditionally disable MDS mitigation
Not specifying this option is equivalent to
mds=full.
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index a7e54a91abc4..3f70da3a4e58 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -219,6 +219,7 @@ static void x86_amd_ssb_disable(void)
/* Default mitigation for L1TF-affected CPUs */
static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL;
+static bool mds_nosmt __ro_after_init = false;
static const char * const mds_strings[] = {
[MDS_MITIGATION_OFF] = "Vulnerable",
@@ -236,8 +237,13 @@ static void __init mds_select_mitigation(void)
if (mds_mitigation == MDS_MITIGATION_FULL) {
if (!boot_cpu_has(X86_FEATURE_MD_CLEAR))
mds_mitigation = MDS_MITIGATION_VMWERV;
+
static_branch_enable(&mds_user_clear);
+
+ if (mds_nosmt && !boot_cpu_has(X86_BUG_MSBDS_ONLY))
+ cpu_smt_disable(false);
}
+
pr_info("%s\n", mds_strings[mds_mitigation]);
}
@@ -253,6 +259,10 @@ static int __init mds_cmdline(char *str)
mds_mitigation = MDS_MITIGATION_OFF;
else if (!strcmp(str, "full"))
mds_mitigation = MDS_MITIGATION_FULL;
+ else if (!strcmp(str, "full,nosmt")) {
+ mds_mitigation = MDS_MITIGATION_FULL;
+ mds_nosmt = true;
+ }
return 0;
}

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@ -0,0 +1,43 @@
From 39a5de311379c9c80f0886522296d08121582cad Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 2 Apr 2019 10:00:14 -0500
Subject: [PATCH 19/30] x86/speculation: Move arch_smt_update() call to after
mitigation decisions
commit 7c3658b20194a5b3209a143f63bc9c643c6a3ae2 upstream
arch_smt_update() now has a dependency on both Spectre v2 and MDS
mitigations. Move its initial call to after all the mitigation decisions
have been made.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
---
arch/x86/kernel/cpu/bugs.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 3f70da3a4e58..6ccbcac2cb1d 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -109,6 +109,8 @@ void __init check_bugs(void)
mds_select_mitigation();
+ arch_smt_update();
+
#ifdef CONFIG_X86_32
/*
* Check whether we are able to run this kernel safely on SMP.
@@ -624,9 +626,6 @@ static void __init spectre_v2_select_mitigation(void)
/* Set up IBPB and STIBP depending on the general spectre V2 command */
spectre_v2_user_select_mitigation(cmd);
-
- /* Enable STIBP if appropriate */
- arch_smt_update();
}
static void update_stibp_msr(void * __unused)

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@ -0,0 +1,58 @@
From 7b41a615bd0f13959d9236abd341879c80379069 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 2 Apr 2019 10:00:51 -0500
Subject: [PATCH 20/30] x86/speculation/mds: Add SMT warning message
commit 39226ef02bfb43248b7db12a4fdccb39d95318e3 upstream
MDS is vulnerable with SMT. Make that clear with a one-time printk
whenever SMT first gets enabled.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
---
arch/x86/kernel/cpu/bugs.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 6ccbcac2cb1d..8e74282da80e 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -659,6 +659,9 @@ static void update_indir_branch_cond(void)
static_branch_disable(&switch_to_cond_stibp);
}
+#undef pr_fmt
+#define pr_fmt(fmt) fmt
+
/* Update the static key controlling the MDS CPU buffer clear in idle */
static void update_mds_branch_idle(void)
{
@@ -679,6 +682,8 @@ static void update_mds_branch_idle(void)
static_branch_disable(&mds_idle_clear);
}
+#define MDS_MSG_SMT "MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.\n"
+
void arch_smt_update(void)
{
/* Enhanced IBRS implies STIBP. No update required. */
@@ -702,6 +707,8 @@ void arch_smt_update(void)
switch (mds_mitigation) {
case MDS_MITIGATION_FULL:
case MDS_MITIGATION_VMWERV:
+ if (sched_smt_active() && !boot_cpu_has(X86_BUG_MSBDS_ONLY))
+ pr_warn_once(MDS_MSG_SMT);
update_mds_branch_idle();
break;
case MDS_MITIGATION_OFF:
@@ -1131,6 +1138,7 @@ static int __init l1tf_cmdline(char *str)
early_param("l1tf", l1tf_cmdline);
#undef pr_fmt
+#define pr_fmt(fmt) fmt
#ifdef CONFIG_SYSFS

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@ -0,0 +1,31 @@
From 7a4591bd67b72f2f6c3e0520f7a670eb3085ccdb Mon Sep 17 00:00:00 2001
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Date: Fri, 12 Apr 2019 17:50:57 -0400
Subject: [PATCH 21/30] x86/speculation/mds: Fix comment
commit cae5ec342645746d617dd420d206e1588d47768a upstream
s/L1TF/MDS/
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/kernel/cpu/bugs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 8e74282da80e..1726f43853ca 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -219,7 +219,7 @@ static void x86_amd_ssb_disable(void)
#undef pr_fmt
#define pr_fmt(fmt) "MDS: " fmt
-/* Default mitigation for L1TF-affected CPUs */
+/* Default mitigation for MDS-affected CPUs */
static enum mds_mitigations mds_mitigation __ro_after_init = MDS_MITIGATION_FULL;
static bool mds_nosmt __ro_after_init = false;

View File

@ -0,0 +1,46 @@
From 902c28c3ffa6271ab3f6f1104b03683eff7c2ac9 Mon Sep 17 00:00:00 2001
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Date: Fri, 12 Apr 2019 17:50:58 -0400
Subject: [PATCH 22/30] x86/speculation/mds: Print SMT vulnerable on MSBDS with
mitigations off
commit e2c3c94788b08891dcf3dbe608f9880523ecd71b upstream
This code is only for CPUs which are affected by MSBDS, but are *not*
affected by the other two MDS issues.
For such CPUs, enabling the mds_idle_clear mitigation is enough to
mitigate SMT.
However if user boots with 'mds=off' and still has SMT enabled, we should
not report that SMT is mitigated:
$cat /sys//devices/system/cpu/vulnerabilities/mds
Vulnerable; SMT mitigated
But rather:
Vulnerable; SMT vulnerable
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20190412215118.294906495@localhost.localdomain
---
arch/x86/kernel/cpu/bugs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 1726f43853ca..8d432a3d38a3 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1186,7 +1186,8 @@ static ssize_t mds_show_state(char *buf)
if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) {
return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
- sched_smt_active() ? "mitigated" : "disabled");
+ (mds_mitigation == MDS_MITIGATION_OFF ? "vulnerable" :
+ sched_smt_active() ? "mitigated" : "disabled"));
}
return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],

View File

@ -0,0 +1,164 @@
From 0e44e1761b78d31665fbce073ce58f42a0ffd4de Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Fri, 12 Apr 2019 15:39:28 -0500
Subject: [PATCH 23/30] cpu/speculation: Add 'mitigations=' cmdline option
commit 98af8452945c55652de68536afdde3b520fec429 upstream
Keeping track of the number of mitigations for all the CPU speculation
bugs has become overwhelming for many users. It's getting more and more
complicated to decide which mitigations are needed for a given
architecture. Complicating matters is the fact that each arch tends to
have its own custom way to mitigate the same vulnerability.
Most users fall into a few basic categories:
a) they want all mitigations off;
b) they want all reasonable mitigations on, with SMT enabled even if
it's vulnerable; or
c) they want all reasonable mitigations on, with SMT disabled if
vulnerable.
Define a set of curated, arch-independent options, each of which is an
aggregation of existing options:
- mitigations=off: Disable all mitigations.
- mitigations=auto: [default] Enable all the default mitigations, but
leave SMT enabled, even if it's vulnerable.
- mitigations=auto,nosmt: Enable all the default mitigations, disabling
SMT if needed by a mitigation.
Currently, these options are placeholders which don't actually do
anything. They will be fleshed out in upcoming patches.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/b07a8ef9b7c5055c3a4637c87d07c296d5016fe0.1555085500.git.jpoimboe@redhat.com
---
.../admin-guide/kernel-parameters.txt | 24 +++++++++++++++++++
include/linux/cpu.h | 24 +++++++++++++++++++
kernel/cpu.c | 15 ++++++++++++
3 files changed, 63 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index df8d10668b11..6a1b94afb005 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2502,6 +2502,30 @@
in the "bleeding edge" mini2440 support kernel at
http://repo.or.cz/w/linux-2.6/mini2440.git
+ mitigations=
+ Control optional mitigations for CPU vulnerabilities.
+ This is a set of curated, arch-independent options, each
+ of which is an aggregation of existing arch-specific
+ options.
+
+ off
+ Disable all optional CPU mitigations. This
+ improves system performance, but it may also
+ expose users to several CPU vulnerabilities.
+
+ auto (default)
+ Mitigate all CPU vulnerabilities, but leave SMT
+ enabled, even if it's vulnerable. This is for
+ users who don't want to be surprised by SMT
+ getting disabled across kernel upgrades, or who
+ have other ways of avoiding SMT-based attacks.
+ This is the default behavior.
+
+ auto,nosmt
+ Mitigate all CPU vulnerabilities, disabling SMT
+ if needed. This is for users who always want to
+ be fully mitigated, even if it means losing SMT.
+
mminit_loglevel=
[KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
parameter allows control of the logging verbosity for
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 3c87ad888ed3..57ae83c4d5f4 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -189,4 +189,28 @@ static inline void cpu_smt_disable(bool force) { }
static inline void cpu_smt_check_topology(void) { }
#endif
+/*
+ * These are used for a global "mitigations=" cmdline option for toggling
+ * optional CPU mitigations.
+ */
+enum cpu_mitigations {
+ CPU_MITIGATIONS_OFF,
+ CPU_MITIGATIONS_AUTO,
+ CPU_MITIGATIONS_AUTO_NOSMT,
+};
+
+extern enum cpu_mitigations cpu_mitigations;
+
+/* mitigations=off */
+static inline bool cpu_mitigations_off(void)
+{
+ return cpu_mitigations == CPU_MITIGATIONS_OFF;
+}
+
+/* mitigations=auto,nosmt */
+static inline bool cpu_mitigations_auto_nosmt(void)
+{
+ return cpu_mitigations == CPU_MITIGATIONS_AUTO_NOSMT;
+}
+
#endif /* _LINUX_CPU_H_ */
diff --git a/kernel/cpu.c b/kernel/cpu.c
index dc250ec2c096..bc6c880a093f 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -2278,3 +2278,18 @@ void __init boot_cpu_hotplug_init(void)
#endif
this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);
}
+
+enum cpu_mitigations cpu_mitigations __ro_after_init = CPU_MITIGATIONS_AUTO;
+
+static int __init mitigations_parse_cmdline(char *arg)
+{
+ if (!strcmp(arg, "off"))
+ cpu_mitigations = CPU_MITIGATIONS_OFF;
+ else if (!strcmp(arg, "auto"))
+ cpu_mitigations = CPU_MITIGATIONS_AUTO;
+ else if (!strcmp(arg, "auto,nosmt"))
+ cpu_mitigations = CPU_MITIGATIONS_AUTO_NOSMT;
+
+ return 0;
+}
+early_param("mitigations", mitigations_parse_cmdline);

View File

@ -0,0 +1,151 @@
From d0bf64abd7f837c5faf16e0550d678aed630e520 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Fri, 12 Apr 2019 15:39:29 -0500
Subject: [PATCH 24/30] x86/speculation: Support 'mitigations=' cmdline option
commit d68be4c4d31295ff6ae34a8ddfaa4c1a8ff42812 upstream
Configure x86 runtime CPU speculation bug mitigations in accordance with
the 'mitigations=' cmdline option. This affects Meltdown, Spectre v2,
Speculative Store Bypass, and L1TF.
The default behavior is unchanged.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/6616d0ae169308516cfdf5216bedd169f8a8291b.1555085500.git.jpoimboe@redhat.com
---
Documentation/admin-guide/kernel-parameters.txt | 16 +++++++++++-----
arch/x86/kernel/cpu/bugs.c | 11 +++++++++--
arch/x86/mm/pti.c | 4 +++-
3 files changed, 23 insertions(+), 8 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6a1b94afb005..31c17532c219 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2503,15 +2503,20 @@
http://repo.or.cz/w/linux-2.6/mini2440.git
mitigations=
- Control optional mitigations for CPU vulnerabilities.
- This is a set of curated, arch-independent options, each
- of which is an aggregation of existing arch-specific
- options.
+ [X86] Control optional mitigations for CPU
+ vulnerabilities. This is a set of curated,
+ arch-independent options, each of which is an
+ aggregation of existing arch-specific options.
off
Disable all optional CPU mitigations. This
improves system performance, but it may also
expose users to several CPU vulnerabilities.
+ Equivalent to: nopti [X86]
+ nospectre_v2 [X86]
+ spectre_v2_user=off [X86]
+ spec_store_bypass_disable=off [X86]
+ l1tf=off [X86]
auto (default)
Mitigate all CPU vulnerabilities, but leave SMT
@@ -2519,12 +2524,13 @@
users who don't want to be surprised by SMT
getting disabled across kernel upgrades, or who
have other ways of avoiding SMT-based attacks.
- This is the default behavior.
+ Equivalent to: (default behavior)
auto,nosmt
Mitigate all CPU vulnerabilities, disabling SMT
if needed. This is for users who always want to
be fully mitigated, even if it means losing SMT.
+ Equivalent to: l1tf=flush,nosmt [X86]
mminit_loglevel=
[KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 8d432a3d38a3..904d55cf80a2 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -494,7 +494,8 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
char arg[20];
int ret, i;
- if (cmdline_find_option_bool(boot_command_line, "nospectre_v2"))
+ if (cmdline_find_option_bool(boot_command_line, "nospectre_v2") ||
+ cpu_mitigations_off())
return SPECTRE_V2_CMD_NONE;
ret = cmdline_find_option(boot_command_line, "spectre_v2", arg, sizeof(arg));
@@ -756,7 +757,8 @@ static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void)
char arg[20];
int ret, i;
- if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable")) {
+ if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable") ||
+ cpu_mitigations_off()) {
return SPEC_STORE_BYPASS_CMD_NONE;
} else {
ret = cmdline_find_option(boot_command_line, "spec_store_bypass_disable",
@@ -1077,6 +1079,11 @@ static void __init l1tf_select_mitigation(void)
if (!boot_cpu_has_bug(X86_BUG_L1TF))
return;
+ if (cpu_mitigations_off())
+ l1tf_mitigation = L1TF_MITIGATION_OFF;
+ else if (cpu_mitigations_auto_nosmt())
+ l1tf_mitigation = L1TF_MITIGATION_FLUSH_NOSMT;
+
override_cache_bits(&boot_cpu_data);
switch (l1tf_mitigation) {
diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
index c1fc1ae6b429..4df3e5c89d57 100644
--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -35,6 +35,7 @@
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
+#include <linux/cpu.h>
#include <asm/cpufeature.h>
#include <asm/hypervisor.h>
@@ -115,7 +116,8 @@ void __init pti_check_boottime_disable(void)
}
}
- if (cmdline_find_option_bool(boot_command_line, "nopti")) {
+ if (cmdline_find_option_bool(boot_command_line, "nopti") ||
+ cpu_mitigations_off()) {
pti_mode = PTI_FORCE_OFF;
pti_print_if_insecure("disabled on command line.");
return;

View File

@ -0,0 +1,122 @@
From 7cd777a49624b9e186919a5e1b7fec49dafdb8eb Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Fri, 12 Apr 2019 15:39:30 -0500
Subject: [PATCH 25/30] powerpc/speculation: Support 'mitigations=' cmdline
option
commit 782e69efb3dfed6e8360bc612e8c7827a901a8f9 upstream
Configure powerpc CPU runtime speculation bug mitigations in accordance
with the 'mitigations=' cmdline option. This affects Meltdown, Spectre
v1, Spectre v2, and Speculative Store Bypass.
The default behavior is unchanged.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/245a606e1a42a558a310220312d9b6adb9159df6.1555085500.git.jpoimboe@redhat.com
---
Documentation/admin-guide/kernel-parameters.txt | 9 +++++----
arch/powerpc/kernel/security.c | 6 +++---
arch/powerpc/kernel/setup_64.c | 2 +-
3 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 31c17532c219..49aa191979c1 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2503,7 +2503,7 @@
http://repo.or.cz/w/linux-2.6/mini2440.git
mitigations=
- [X86] Control optional mitigations for CPU
+ [X86,PPC] Control optional mitigations for CPU
vulnerabilities. This is a set of curated,
arch-independent options, each of which is an
aggregation of existing arch-specific options.
@@ -2512,10 +2512,11 @@
Disable all optional CPU mitigations. This
improves system performance, but it may also
expose users to several CPU vulnerabilities.
- Equivalent to: nopti [X86]
- nospectre_v2 [X86]
+ Equivalent to: nopti [X86,PPC]
+ nospectre_v1 [PPC]
+ nospectre_v2 [X86,PPC]
spectre_v2_user=off [X86]
- spec_store_bypass_disable=off [X86]
+ spec_store_bypass_disable=off [X86,PPC]
l1tf=off [X86]
auto (default)
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 1341325599a7..4ccbf611a3c5 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -56,7 +56,7 @@ void setup_barrier_nospec(void)
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR);
- if (!no_nospec)
+ if (!no_nospec && !cpu_mitigations_off())
enable_barrier_nospec(enable);
}
@@ -115,7 +115,7 @@ static int __init handle_nospectre_v2(char *p)
early_param("nospectre_v2", handle_nospectre_v2);
void setup_spectre_v2(void)
{
- if (no_spectrev2)
+ if (no_spectrev2 || cpu_mitigations_off())
do_btb_flush_fixups();
else
btb_flush_enabled = true;
@@ -299,7 +299,7 @@ void setup_stf_barrier(void)
stf_enabled_flush_types = type;
- if (!no_stf_barrier)
+ if (!no_stf_barrier && !cpu_mitigations_off())
stf_barrier_enable(enable);
}
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index faf00222b324..eaf7300be5ab 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -955,7 +955,7 @@ void setup_rfi_flush(enum l1d_flush_type types, bool enable)
enabled_flush_types = types;
- if (!no_rfi_flush)
+ if (!no_rfi_flush && !cpu_mitigations_off())
rfi_flush_enable(enable);
}

View File

@ -0,0 +1,92 @@
From cf0b4c8e4d70fe1d282b4e910834f3982ca10eb4 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Fri, 12 Apr 2019 15:39:31 -0500
Subject: [PATCH 26/30] s390/speculation: Support 'mitigations=' cmdline option
commit 0336e04a6520bdaefdb0769d2a70084fa52e81ed upstream
Configure s390 runtime CPU speculation bug mitigations in accordance
with the 'mitigations=' cmdline option. This affects Spectre v1 and
Spectre v2.
The default behavior is unchanged.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Kosina <jkosina@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/e4a161805458a5ec88812aac0307ae3908a030fc.1555085500.git.jpoimboe@redhat.com
---
Documentation/admin-guide/kernel-parameters.txt | 5 +++--
arch/s390/kernel/nospec-branch.c | 3 ++-
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 49aa191979c1..4f3efaaa46bd 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2503,7 +2503,7 @@
http://repo.or.cz/w/linux-2.6/mini2440.git
mitigations=
- [X86,PPC] Control optional mitigations for CPU
+ [X86,PPC,S390] Control optional mitigations for CPU
vulnerabilities. This is a set of curated,
arch-independent options, each of which is an
aggregation of existing arch-specific options.
@@ -2514,7 +2514,8 @@
expose users to several CPU vulnerabilities.
Equivalent to: nopti [X86,PPC]
nospectre_v1 [PPC]
- nospectre_v2 [X86,PPC]
+ nobp=0 [S390]
+ nospectre_v2 [X86,PPC,S390]
spectre_v2_user=off [X86]
spec_store_bypass_disable=off [X86,PPC]
l1tf=off [X86]
diff --git a/arch/s390/kernel/nospec-branch.c b/arch/s390/kernel/nospec-branch.c
index bdddaae96559..649135cbedd5 100644
--- a/arch/s390/kernel/nospec-branch.c
+++ b/arch/s390/kernel/nospec-branch.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/module.h>
#include <linux/device.h>
+#include <linux/cpu.h>
#include <asm/nospec-branch.h>
static int __init nobp_setup_early(char *str)
@@ -58,7 +59,7 @@ early_param("nospectre_v2", nospectre_v2_setup_early);
void __init nospec_auto_detect(void)
{
- if (test_facility(156)) {
+ if (test_facility(156) || cpu_mitigations_off()) {
/*
* The machine supports etokens.
* Disable expolines and disable nobp.

View File

@ -0,0 +1,59 @@
From d15a5678215ac4702f48d739ca3653ad1e568b52 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Wed, 17 Apr 2019 16:39:02 -0500
Subject: [PATCH 27/30] x86/speculation/mds: Add 'mitigations=' support for MDS
commit 5c14068f87d04adc73ba3f41c2a303d3c3d1fa12 upstream
Add MDS to the new 'mitigations=' cmdline option.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/admin-guide/kernel-parameters.txt | 2 ++
arch/x86/kernel/cpu/bugs.c | 5 +++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4f3efaaa46bd..a29301d6e6c6 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2519,6 +2519,7 @@
spectre_v2_user=off [X86]
spec_store_bypass_disable=off [X86,PPC]
l1tf=off [X86]
+ mds=off [X86]
auto (default)
Mitigate all CPU vulnerabilities, but leave SMT
@@ -2533,6 +2534,7 @@
if needed. This is for users who always want to
be fully mitigated, even if it means losing SMT.
Equivalent to: l1tf=flush,nosmt [X86]
+ mds=full,nosmt [X86]
mminit_loglevel=
[KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 904d55cf80a2..9b096f26d1c8 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -231,7 +231,7 @@ static const char * const mds_strings[] = {
static void __init mds_select_mitigation(void)
{
- if (!boot_cpu_has_bug(X86_BUG_MDS)) {
+ if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off()) {
mds_mitigation = MDS_MITIGATION_OFF;
return;
}
@@ -242,7 +242,8 @@ static void __init mds_select_mitigation(void)
static_branch_enable(&mds_user_clear);
- if (mds_nosmt && !boot_cpu_has(X86_BUG_MSBDS_ONLY))
+ if (!boot_cpu_has(X86_BUG_MSBDS_ONLY) &&
+ (mds_nosmt || cpu_mitigations_auto_nosmt()))
cpu_smt_disable(false);
}

View File

@ -0,0 +1,69 @@
From ce4dbfe6007776bac14b2435bcf7c17976daeafe Mon Sep 17 00:00:00 2001
From: speck for Pawan Gupta <speck@linutronix.de>
Date: Mon, 6 May 2019 12:23:50 -0700
Subject: [PATCH 28/30] x86/mds: Add MDSUM variant to the MDS documentation
commit e672f8bf71c66253197e503f75c771dd28ada4a0 upstream
Updated the documentation for a new CVE-2019-11091 Microarchitectural Data
Sampling Uncacheable Memory (MDSUM) which is a variant of
Microarchitectural Data Sampling (MDS). MDS is a family of side channel
attacks on internal buffers in Intel CPUs.
MDSUM is a special case of MSBDS, MFBDS and MLPDS. An uncacheable load from
memory that takes a fault or assist can leave data in a microarchitectural
structure that may later be observed using one of the same methods used by
MSBDS, MFBDS or MLPDS. There are no new code changes expected for MDSUM.
The existing mitigation for MDS applies to MDSUM as well.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Jon Masters <jcm@redhat.com>
---
Documentation/admin-guide/hw-vuln/mds.rst | 5 +++--
Documentation/x86/mds.rst | 5 +++++
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/Documentation/admin-guide/hw-vuln/mds.rst b/Documentation/admin-guide/hw-vuln/mds.rst
index 244ab47d1fb3..e0dccf414eca 100644
--- a/Documentation/admin-guide/hw-vuln/mds.rst
+++ b/Documentation/admin-guide/hw-vuln/mds.rst
@@ -32,11 +32,12 @@ Related CVEs
The following CVE entries are related to the MDS vulnerability:
- ============== ===== ==============================================
+ ============== ===== ===================================================
CVE-2018-12126 MSBDS Microarchitectural Store Buffer Data Sampling
CVE-2018-12130 MFBDS Microarchitectural Fill Buffer Data Sampling
CVE-2018-12127 MLPDS Microarchitectural Load Port Data Sampling
- ============== ===== ==============================================
+ CVE-2019-11091 MDSUM Microarchitectural Data Sampling Uncacheable Memory
+ ============== ===== ===================================================
Problem
-------
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 3d6f943f1afb..979945be257a 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -12,6 +12,7 @@ Microarchitectural Data Sampling (MDS) is a family of side channel attacks
- Microarchitectural Store Buffer Data Sampling (MSBDS) (CVE-2018-12126)
- Microarchitectural Fill Buffer Data Sampling (MFBDS) (CVE-2018-12130)
- Microarchitectural Load Port Data Sampling (MLPDS) (CVE-2018-12127)
+ - Microarchitectural Data Sampling Uncacheable Memory (MDSUM) (CVE-2019-11091)
MSBDS leaks Store Buffer Entries which can be speculatively forwarded to a
dependent load (store-to-load forwarding) as an optimization. The forward
@@ -38,6 +39,10 @@ faulting or assisting loads under certain conditions, which again can be
exploited eventually. Load ports are shared between Hyper-Threads so cross
thread leakage is possible.
+MDSUM is a special case of MSBDS, MFBDS and MLPDS. An uncacheable load from
+memory that takes a fault or assist can leave data in a microarchitectural
+structure that may later be observed using one of the same methods used by
+MSBDS, MFBDS or MLPDS.
Exposure assumptions
--------------------

View File

@ -0,0 +1,62 @@
From 9cd0e06f7739f9e1a15379e971b3e6c64816d36f Mon Sep 17 00:00:00 2001
From: Tyler Hicks <tyhicks@canonical.com>
Date: Mon, 6 May 2019 23:52:58 +0000
Subject: [PATCH 29/30] Documentation: Correct the possible MDS sysfs values
commit ea01668f9f43021b28b3f4d5ffad50106a1e1301 upstream
Adjust the last two rows in the table that display possible values when
MDS mitigation is enabled. They both were slightly innacurate.
In addition, convert the table of possible values and their descriptions
to a list-table. The simple table format uses the top border of equals
signs to determine cell width which resulted in the first column being
far too wide in comparison to the second column that contained the
majority of the text.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/admin-guide/hw-vuln/mds.rst | 29 ++++++++++-------------
1 file changed, 13 insertions(+), 16 deletions(-)
diff --git a/Documentation/admin-guide/hw-vuln/mds.rst b/Documentation/admin-guide/hw-vuln/mds.rst
index e0dccf414eca..e3a796c0d3a2 100644
--- a/Documentation/admin-guide/hw-vuln/mds.rst
+++ b/Documentation/admin-guide/hw-vuln/mds.rst
@@ -95,22 +95,19 @@ status of the system: whether the system is vulnerable, and which
The possible values in this file are:
- ========================================= =================================
- 'Not affected' The processor is not vulnerable
-
- 'Vulnerable' The processor is vulnerable,
- but no mitigation enabled
-
- 'Vulnerable: Clear CPU buffers attempted' The processor is vulnerable but
- microcode is not updated.
- The mitigation is enabled on a
- best effort basis.
- See :ref:`vmwerv`
-
- 'Mitigation: CPU buffer clear' The processor is vulnerable and the
- CPU buffer clearing mitigation is
- enabled.
- ========================================= =================================
+ .. list-table::
+
+ * - 'Not affected'
+ - The processor is not vulnerable
+ * - 'Vulnerable'
+ - The processor is vulnerable, but no mitigation enabled
+ * - 'Vulnerable: Clear CPU buffers attempted, no microcode'
+ - The processor is vulnerable but microcode is not updated.
+
+ The mitigation is enabled on a best effort basis. See :ref:`vmwerv`
+ * - 'Mitigation: Clear CPU buffers'
+ - The processor is vulnerable and the CPU buffer clearing mitigation is
+ enabled.
If the processor is vulnerable then the following information is appended
to the above information:

View File

@ -0,0 +1,29 @@
From 011c5b50bb2e545174b2bcd1452b4f1a099e79b0 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 7 May 2019 15:05:22 -0500
Subject: [PATCH 30/30] x86/speculation/mds: Fix documentation typo
commit 95310e348a321b45fb746c176961d4da72344282 upstream
Fix a minor typo in the MDS documentation: "eanbled" -> "enabled".
Reported-by: Jeff Bastian <jbastian@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
Documentation/x86/mds.rst | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/x86/mds.rst b/Documentation/x86/mds.rst
index 979945be257a..534e9baa4e1d 100644
--- a/Documentation/x86/mds.rst
+++ b/Documentation/x86/mds.rst
@@ -116,7 +116,7 @@ Kernel internal mitigation modes
off Mitigation is disabled. Either the CPU is not affected or
mds=off is supplied on the kernel command line
- full Mitigation is eanbled. CPU is affected and MD_CLEAR is
+ full Mitigation is enabled. CPU is affected and MD_CLEAR is
advertised in CPUID.
vmwerv Mitigation is enabled. CPU is affected and MD_CLEAR is not

30
debian/patches/series vendored
View File

@ -181,6 +181,36 @@ bugfix/all/0001-mm-make-page-ref-count-overflow-check-tighter-and-mo.patch
bugfix/all/0002-mm-add-try_get_page-helper-function.patch
bugfix/all/0003-mm-prevent-get_user_pages-from-overflowing-page-refc.patch
bugfix/all/0004-fs-prevent-page-refcount-overflow-in-pipe_buf_get.patch
bugfix/all/spec/0001-Documentation-l1tf-Fix-small-spelling-typo.patch
bugfix/all/spec/0002-x86-cpu-Sanitize-FAM6_ATOM-naming.patch
bugfix/all/spec/0003-kvm-x86-Report-STIBP-on-GET_SUPPORTED_CPUID.patch
bugfix/all/spec/0004-x86-msr-index-Cleanup-bit-defines.patch
bugfix/all/spec/0005-x86-speculation-Consolidate-CPU-whitelists.patch
bugfix/all/spec/0006-x86-speculation-mds-Add-basic-bug-infrastructure-for.patch
bugfix/all/spec/0007-x86-speculation-mds-Add-BUG_MSBDS_ONLY.patch
bugfix/all/spec/0008-x86-kvm-Expose-X86_FEATURE_MD_CLEAR-to-guests.patch
bugfix/all/spec/0009-x86-speculation-mds-Add-mds_clear_cpu_buffers.patch
bugfix/all/spec/0010-x86-speculation-mds-Clear-CPU-buffers-on-exit-to-use.patch
bugfix/all/spec/0011-x86-kvm-vmx-Add-MDS-protection-when-L1D-Flush-is-not.patch
bugfix/all/spec/0012-x86-speculation-mds-Conditionally-clear-CPU-buffers-.patch
bugfix/all/spec/0013-x86-speculation-mds-Add-mitigation-control-for-MDS.patch
bugfix/all/spec/0014-x86-speculation-mds-Add-sysfs-reporting-for-MDS.patch
bugfix/all/spec/0015-x86-speculation-mds-Add-mitigation-mode-VMWERV.patch
bugfix/all/spec/0016-Documentation-Move-L1TF-to-separate-directory.patch
bugfix/all/spec/0017-Documentation-Add-MDS-vulnerability-documentation.patch
bugfix/all/spec/0018-x86-speculation-mds-Add-mds-full-nosmt-cmdline-optio.patch
bugfix/all/spec/0019-x86-speculation-Move-arch_smt_update-call-to-after-m.patch
bugfix/all/spec/0020-x86-speculation-mds-Add-SMT-warning-message.patch
bugfix/all/spec/0021-x86-speculation-mds-Fix-comment.patch
bugfix/all/spec/0022-x86-speculation-mds-Print-SMT-vulnerable-on-MSBDS-wi.patch
bugfix/all/spec/0023-cpu-speculation-Add-mitigations-cmdline-option.patch
bugfix/all/spec/0024-x86-speculation-Support-mitigations-cmdline-option.patch
bugfix/all/spec/0025-powerpc-speculation-Support-mitigations-cmdline-opti.patch
bugfix/all/spec/0026-s390-speculation-Support-mitigations-cmdline-option.patch
bugfix/all/spec/0027-x86-speculation-mds-Add-mitigations-support-for-MDS.patch
bugfix/all/spec/0028-x86-mds-Add-MDSUM-variant-to-the-MDS-documentation.patch
bugfix/all/spec/0029-Documentation-Correct-the-possible-MDS-sysfs-values.patch
bugfix/all/spec/0030-x86-speculation-mds-Fix-documentation-typo.patch
# Fix exported symbol versions
bugfix/all/module-disable-matching-missing-version-crc.patch