4.1-stable patches

added patches:
	mm-slab-fix-unexpected-index-mapping-result-of-kmalloc_size-index_node-1.patch

diff --git a/queue-4.1/mm-slab-fix-unexpected-index-mapping-result-of-kmalloc_size-index_node-1.patch b/queue-4.1/mm-slab-fix-unexpected-index-mapping-result-of-kmalloc_size-index_node-1.patch
new file mode 100644 (file)
index 0000000..611a097
--- /dev/null
+++ b/queue-4.1/mm-slab-fix-unexpected-index-mapping-result-of-kmalloc_size-index_node-1.patch
@@ -0,0 +1,90 @@
+From 03a2d2a3eafe4015412cf4e9675ca0e2d9204074 Mon Sep 17 00:00:00 2001
+From: Joonsoo Kim <js1304@gmail.com>
+Date: Thu, 1 Oct 2015 15:36:54 -0700
+Subject: mm/slab: fix unexpected index mapping result of kmalloc_size(INDEX_NODE+1)
+
+From: Joonsoo Kim <js1304@gmail.com>
+
+commit 03a2d2a3eafe4015412cf4e9675ca0e2d9204074 upstream.
+
+Commit description is copied from the original post of this bug:
+
+  http://comments.gmane.org/gmane.linux.kernel.mm/135349
+
+Kernels after v3.9 use kmalloc_size(INDEX_NODE + 1) to get the next
+larger cache size than the size index INDEX_NODE mapping.  In kernels
+3.9 and earlier we used malloc_sizes[INDEX_L3 + 1].cs_size.
+
+However, sometimes we can't get the right output we expected via
+kmalloc_size(INDEX_NODE + 1), causing a BUG().
+
+The mapping table in the latest kernel is like:
+    index = {0,   1,  2 ,  3,  4,   5,   6,   n}
+     size = {0,   96, 192, 8, 16,  32,  64,   2^n}
+The mapping table before 3.10 is like this:
+    index = {0 , 1 , 2,   3,  4 ,  5 ,  6,   n}
+    size  = {32, 64, 96, 128, 192, 256, 512, 2^(n+3)}
+
+The problem on my mips64 machine is as follows:
+
+(1) When configured DEBUG_SLAB && DEBUG_PAGEALLOC && DEBUG_LOCK_ALLOC
+    && DEBUG_SPINLOCK, the sizeof(struct kmem_cache_node) will be "150",
+    and the macro INDEX_NODE turns out to be "2": #define INDEX_NODE
+    kmalloc_index(sizeof(struct kmem_cache_node))
+
+(2) Then the result of kmalloc_size(INDEX_NODE + 1) is 8.
+
+(3) Then "if(size >= kmalloc_size(INDEX_NODE + 1)" will lead to "size
+    = PAGE_SIZE".
+
+(4) Then "if ((size >= (PAGE_SIZE >> 3))" test will be satisfied and
+    "flags |= CFLGS_OFF_SLAB" will be covered.
+
+(5) if (flags & CFLGS_OFF_SLAB)" test will be satisfied and will go to
+    "cachep->slabp_cache = kmalloc_slab(slab_size, 0u)", and the result
+    here may be NULL while kernel bootup.
+
+(6) Finally,"BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache));" causes the
+    BUG info as the following shows (may be only mips64 has this problem):
+
+This patch fixes the problem of kmalloc_size(INDEX_NODE + 1) and removes
+the BUG by adding 'size >= 256' check to guarantee that all necessary
+small sized slabs are initialized regardless sequence of slab size in
+mapping table.
+
+Fixes: e33660165c90 ("slab: Use common kmalloc_index/kmalloc_size...")
+Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
+Reported-by: Liuhailong <liu.hailong6@zte.com.cn>
+Acked-by: Christoph Lameter <cl@linux.com>
+Cc: Pekka Enberg <penberg@kernel.org>
+Cc: David Rientjes <rientjes@google.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ mm/slab.c |   13 ++++++++++---
+ 1 file changed, 10 insertions(+), 3 deletions(-)
+
+--- a/mm/slab.c
++++ b/mm/slab.c
+@@ -2189,9 +2189,16 @@ __kmem_cache_create (struct kmem_cache *
+                       size += BYTES_PER_WORD;
+       }
+ #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC)
+-      if (size >= kmalloc_size(INDEX_NODE + 1)
+-          && cachep->object_size > cache_line_size()
+-          && ALIGN(size, cachep->align) < PAGE_SIZE) {
++      /*
++       * To activate debug pagealloc, off-slab management is necessary
++       * requirement. In early phase of initialization, small sized slab
++       * doesn't get initialized so it would not be possible. So, we need
++       * to check size >= 256. It guarantees that all necessary small
++       * sized slab is initialized in current slab initialization sequence.
++       */
++      if (!slab_early_init && size >= kmalloc_size(INDEX_NODE) &&
++              size >= 256 && cachep->object_size > cache_line_size() &&
++              ALIGN(size, cachep->align) < PAGE_SIZE) {
+               cachep->obj_offset += PAGE_SIZE - ALIGN(size, cachep->align);
+               size = PAGE_SIZE;
+       }

diff --git a/queue-4.1/series b/queue-4.1/series
index 85d95ed5582585bf1fb286df6788d24094c87601..08e41b9a5195c5568b21476e2625e75caae59c6d 100644 (file)
--- a/queue-4.1/series
+++ b/queue-4.1/series
@@ -197,3 +197,4 @@ drivers-tty-require-read-access-for-controlling-terminal.patch
 serial-8250-add-uart_config-entry-for-port_rt2880.patch
 serial-atmel-fix-error-path-of-probe-function.patch
 intel_pstate-fix-overflow-in-busy_scaled-due-to-long-delay.patch
+mm-slab-fix-unexpected-index-mapping-result-of-kmalloc_size-index_node-1.patch