Cherry-pick ZONE_DEVICE changes from linux-next

2016-03-25 13:45:59 +00:00 · 2016-03-25 13:45:59 +00:00 · d3da98fed6
parent 9bbc2cf793
commit d3da98fed6
4 changed files with 160 additions and 0 deletions
--- a/debian/changelog
+++ b/debian/changelog
@ -1,3 +1,10 @@
+linux (4.5-1~exp2) UNRELEASED; urgency=medium
+
+  * mm: exclude ZONE_DEVICE from GFP_ZONE_TABLE
+  * mm: ZONE_DEVICE depends on SPARSEMEM_VMEMMAP
+
+ -- Ben Hutchings <ben@decadent.org.uk>  Fri, 25 Mar 2016 13:43:57 +0000
+
 linux (4.5-1~exp1) experimental; urgency=medium

  * New upstream release: http://kernelnewbies.org/Linux_4.5
--- a/debian/patches/bugfix/all/mm-zone_device-depends-on-sparsemem_vmemmap.patch
+++ b/debian/patches/bugfix/all/mm-zone_device-depends-on-sparsemem_vmemmap.patch
@ -0,0 +1,36 @@
+From: Dan Williams <dan.j.williams@intel.com>
+Date: Wed, 16 Mar 2016 14:16:28 +1100
+Subject: mm: ZONE_DEVICE depends on SPARSEMEM_VMEMMAP
+Origin: http://article.gmane.org/gmane.linux.kernel.mm/147702
+
+The primary use case for devm_memremap_pages() is to allocate an memmap
+array from persistent memory.  That capabilty requires vmem_altmap which
+requires SPARSEMEM_VMEMMAP.
+
+Also, without SPARSEMEM_VMEMMAP the addition of ZONE_DEVICE expands
+ZONES_WIDTH and triggers the:
+
+"Unfortunate NUMA and NUMA Balancing config, growing page-frame for
+last_cpupid."
+
+...warning in mm/memory.c.  SPARSEMEM_VMEMMAP=n && ZONE_DEVICE=y is not
+a configuration we should worry about supporting.
+
+Signed-off-by: Dan Williams <dan.j.williams@intel.com>
+Reported-by: Vlastimil Babka <vbabka@suse.cz>
+Acked-by: Vlastimil Babka <vbabka@suse.cz>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+---
+ mm/Kconfig | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/mm/Kconfig
+++ b/mm/Kconfig
+@@ -654,6 +654,7 @@ config ZONE_DEVICE
+ 	bool "Device memory (pmem, etc...) hotplug support" if EXPERT
+ 	depends on MEMORY_HOTPLUG
+ 	depends on MEMORY_HOTREMOVE
+	depends on SPARSEMEM_VMEMMAP
+ 	depends on X86_64 #arch_add_memory() comprehends device memory
+ 
+ 	help
--- a/debian/patches/features/all/mm-exclude-zone_device-from-gfp_zone_table.patch
+++ b/debian/patches/features/all/mm-exclude-zone_device-from-gfp_zone_table.patch
@ -0,0 +1,115 @@
+From: Dan Williams <dan.j.williams@intel.com>
+Date: Wed, 16 Mar 2016 14:16:26 +1100
+Subject: mm: exclude ZONE_DEVICE from GFP_ZONE_TABLE
+Origin: http://article.gmane.org/gmane.linux.kernel.mm/147399
+
+ZONE_DEVICE (merged in 4.3) and ZONE_CMA (proposed) are examples of new mm
+zones that are bumping up against the current maximum limit of 4 zones,
+i.e.  2 bits in page->flags for the GFP_ZONE_TABLE.
+
+The GFP_ZONE_TABLE poses an interesting constraint since
+include/linux/gfp.h gets included by the 32-bit portion of a 64-bit build.
+We need to be careful to only build the table for zones that have a
+corresponding gfp_t flag.  GFP_ZONES_SHIFT is introduced for this purpose.
+This patch does not attempt to solve the problem of adding a new zone
+that also has a corresponding GFP_ flag.
+
+Vlastimil points out that ZONE_DEVICE, by depending on x86_64 and
+SPARSEMEM_VMEMMAP implies that SECTIONS_WIDTH is zero.  In other words
+even though ZONE_DEVICE does not fit in GFP_ZONE_TABLE it is free to
+consume another bit in page->flags (expand ZONES_WIDTH) with room to
+spare.
+
+Link: https://bugzilla.kernel.org/show_bug.cgi?id=110931
+Fixes: 033fbae988fc ("mm: ZONE_DEVICE for "device memory"")
+Signed-off-by: Dan Williams <dan.j.williams@intel.com>
+Reported-by: Mark <markk@clara.co.uk>
+Reported-by: Vlastimil Babka <vbabka@suse.cz>
+Cc: Mel Gorman <mgorman@suse.de>
+Cc: Rik van Riel <riel@redhat.com>
+Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
+Cc: Dave Hansen <dave.hansen@linux.intel.com>
+Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+---
+ include/linux/gfp.h               | 33 ++++++++++++++++++++-------------
+ include/linux/page-flags-layout.h |  2 ++
+ mm/Kconfig                        |  2 --
+ 3 files changed, 22 insertions(+), 15 deletions(-)
+
+--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
+@@ -329,22 +329,29 @@ static inline bool gfpflags_allow_blocki
+  *       0xe    => BAD (MOVABLE+DMA32+HIGHMEM)
+  *       0xf    => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
+  *
+- * ZONES_SHIFT must be <= 2 on 32 bit platforms.
+ * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
+  */
+ 
+-#if 16 * ZONES_SHIFT > BITS_PER_LONG
+-#error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
+#if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
+/* ZONE_DEVICE is not a valid GFP zone specifier */
+#define GFP_ZONES_SHIFT 2
+#else
+#define GFP_ZONES_SHIFT ZONES_SHIFT
+#endif
+
+#if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
+#error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
+ #endif
+ 
+ #define GFP_ZONE_TABLE ( \
+-	(ZONE_NORMAL << 0 * ZONES_SHIFT)				      \
+-	| (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT)			      \
+-	| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT)		      \
+-	| (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT)		      \
+-	| (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT)			      \
+-	| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT)	      \
+-	| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT)   \
+-	| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT)   \
+	(ZONE_NORMAL << 0 * GFP_ZONES_SHIFT)				       \
+	| (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT)		       \
+	| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT)	       \
+	| (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT)		       \
+	| (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT)		       \
+	| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT)    \
+	| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
+	| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
+ )
+ 
+ /*
+@@ -369,8 +376,8 @@ static inline enum zone_type gfp_zone(gf
+ 	enum zone_type z;
+ 	int bit = (__force int) (flags & GFP_ZONEMASK);
+ 
+-	z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
+-					 ((1 << ZONES_SHIFT) - 1);
+	z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
+					 ((1 << GFP_ZONES_SHIFT) - 1);
+ 	VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
+ 	return z;
+ }
+--- a/include/linux/page-flags-layout.h
+++ b/include/linux/page-flags-layout.h
+@@ -17,6 +17,8 @@
+ #define ZONES_SHIFT 1
+ #elif MAX_NR_ZONES <= 4
+ #define ZONES_SHIFT 2
+#elif MAX_NR_ZONES <= 8
+#define ZONES_SHIFT 3
+ #else
+ #error ZONES_SHIFT -- too many zones configured adjust calculation
+ #endif
+--- a/mm/Kconfig
+++ b/mm/Kconfig
+@@ -652,8 +652,6 @@ config IDLE_PAGE_TRACKING
+ 
+ config ZONE_DEVICE
+ 	bool "Device memory (pmem, etc...) hotplug support" if EXPERT
+-	default !ZONE_DMA
+-	depends on !ZONE_DMA
+ 	depends on MEMORY_HOTPLUG
+ 	depends on MEMORY_HOTREMOVE
+ 	depends on X86_64 #arch_add_memory() comprehends device memory
--- a/debian/patches/series
+++ b/debian/patches/series
@ -87,3 +87,5 @@ bugfix/all/uas-fix-high-order-alloc.patch
 bugfix/x86/x86-mm-pat-fix-boot-crash-when-1gb-pages-are-not-supported.patch
 bugfix/all/netfilter-x_tables-check-for-size-overflow.patch
 bugfix/x86/vmxnet3-fix-lock-imbalance-in-vmxnet3_tq_xmit.patch
+features/all/mm-exclude-zone_device-from-gfp_zone_table.patch
+bugfix/all/mm-zone_device-depends-on-sparsemem_vmemmap.patch