linux/debian/patches/bugfix/x86/taa/0017-TAAv6-5.patch

120 lines
4.2 KiB
Diff

From: speck for Pawan Gupta <speck@linutronix.de>
Date: Wed, 9 Oct 2019 16:26:56 -0700
Subject: TAAv6 5
Add the sysfs reporting file for TSX Async Abort. It exposes the
vulnerability and the mitigation state similar to the existing files for
the other hardware vulnerabilities.
sysfs file path is:
/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Reviewed-by: Mark Gross <mgross@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
[bwh: Forward-ported on top of NX: Fix conflicts (neighbouring
insertions) in arch/x86/kernel/cpu/bugs.c, drivers/base/cpu.c,
include/linux/cpu.h]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/x86/kernel/cpu/bugs.c | 23 +++++++++++++++++++++++
drivers/base/cpu.c | 9 +++++++++
include/linux/cpu.h | 3 +++
3 files changed, 35 insertions(+)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 841f106a277a..c435bc5dc19b 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1439,6 +1439,21 @@ static ssize_t mds_show_state(char *buf)
sched_smt_active() ? "vulnerable" : "disabled");
}
+static ssize_t tsx_async_abort_show_state(char *buf)
+{
+ if ((taa_mitigation == TAA_MITIGATION_TSX_DISABLE) ||
+ (taa_mitigation == TAA_MITIGATION_OFF))
+ return sprintf(buf, "%s\n", taa_strings[taa_mitigation]);
+
+ if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+ return sprintf(buf, "%s; SMT Host state unknown\n",
+ taa_strings[taa_mitigation]);
+ }
+
+ return sprintf(buf, "%s; SMT %s\n", taa_strings[taa_mitigation],
+ sched_smt_active() ? "vulnerable" : "disabled");
+}
+
static char *stibp_state(void)
{
if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
@@ -1510,6 +1525,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
case X86_BUG_ITLB_MULTIHIT:
return itlb_multihit_show_state(buf);
+ case X86_BUG_TAA:
+ return tsx_async_abort_show_state(buf);
+
default:
break;
}
@@ -1551,4 +1569,9 @@ ssize_t cpu_show_itlb_multihit(struct device *dev, struct device_attribute *attr
{
return cpu_show_common(dev, attr, buf, X86_BUG_ITLB_MULTIHIT);
}
+
+ssize_t cpu_show_tsx_async_abort(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_TAA);
+}
#endif
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index c21e2aec5cbb..e9e7fde0fe00 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -558,6 +558,13 @@ ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
return sprintf(buf, "Not affected\n");
}
+ssize_t __weak cpu_show_tsx_async_abort(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);
@@ -565,6 +572,7 @@ 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 DEVICE_ATTR(itlb_multihit, 0444, cpu_show_itlb_multihit, NULL);
+static DEVICE_ATTR(tsx_async_abort, 0444, cpu_show_tsx_async_abort, NULL);
static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_meltdown.attr,
@@ -574,6 +582,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
&dev_attr_l1tf.attr,
&dev_attr_mds.attr,
&dev_attr_itlb_multihit.attr,
+ &dev_attr_tsx_async_abort.attr,
NULL
};
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 7bb824b0f30e..9d8dba19844e 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -61,6 +61,9 @@ extern ssize_t cpu_show_mds(struct device *dev,
struct device_attribute *attr, char *buf);
extern ssize_t cpu_show_itlb_multihit(struct device *dev,
struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_tsx_async_abort(struct device *dev,
+ struct device_attribute *attr,
+ char *buf);
extern __printf(4, 5)
struct device *cpu_device_create(struct device *parent, void *drvdata,