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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-12 01:15:57 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-12 01:15:57 +0400
commit512626a04e72aca60effe111fa0333ed0b195d21 (patch)
treec22e23b0dcc2dd2ff5a9a96a007de6799e9223de /mm/slab.c
parent8a1ca8cedd108c8e76a6ab34079d0bbb4f244799 (diff)
parent3aa27bbe7a6536d1ec859d3a97caf3319b5081b7 (diff)
downloadlinux-512626a04e72aca60effe111fa0333ed0b195d21.tar.xz
Merge branch 'for-linus' of git://linux-arm.org/linux-2.6
* 'for-linus' of git://linux-arm.org/linux-2.6: kmemleak: Add the corresponding MAINTAINERS entry kmemleak: Simple testing module for kmemleak kmemleak: Enable the building of the memory leak detector kmemleak: Remove some of the kmemleak false positives kmemleak: Add modules support kmemleak: Add kmemleak_alloc callback from alloc_large_system_hash kmemleak: Add the vmalloc memory allocation/freeing hooks kmemleak: Add the slub memory allocation/freeing hooks kmemleak: Add the slob memory allocation/freeing hooks kmemleak: Add the slab memory allocation/freeing hooks kmemleak: Add documentation on the memory leak detector kmemleak: Add the base support Manual conflict resolution (with the slab/earlyboot changes) in: drivers/char/vt.c init/main.c mm/slab.c
Diffstat (limited to 'mm/slab.c')
-rw-r--r--mm/slab.c32
1 files changed, 30 insertions, 2 deletions
diff --git a/mm/slab.c b/mm/slab.c
index 2bd611fa87bf..f46b65d124e5 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -107,6 +107,7 @@
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/nodemask.h>
+#include <linux/kmemleak.h>
#include <linux/mempolicy.h>
#include <linux/mutex.h>
#include <linux/fault-inject.h>
@@ -178,13 +179,13 @@
SLAB_STORE_USER | \
SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \
SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD | \
- SLAB_DEBUG_OBJECTS)
+ SLAB_DEBUG_OBJECTS | SLAB_NOLEAKTRACE)
#else
# define CREATE_MASK (SLAB_HWCACHE_ALIGN | \
SLAB_CACHE_DMA | \
SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \
SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD | \
- SLAB_DEBUG_OBJECTS)
+ SLAB_DEBUG_OBJECTS | SLAB_NOLEAKTRACE)
#endif
/*
@@ -964,6 +965,14 @@ static struct array_cache *alloc_arraycache(int node, int entries,
struct array_cache *nc = NULL;
nc = kmalloc_node(memsize, gfp, node);
+ /*
+ * The array_cache structures contain pointers to free object.
+ * However, when such objects are allocated or transfered to another
+ * cache the pointers are not cleared and they could be counted as
+ * valid references during a kmemleak scan. Therefore, kmemleak must
+ * not scan such objects.
+ */
+ kmemleak_no_scan(nc);
if (nc) {
nc->avail = 0;
nc->limit = entries;
@@ -2625,6 +2634,14 @@ static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp,
/* Slab management obj is off-slab. */
slabp = kmem_cache_alloc_node(cachep->slabp_cache,
local_flags, nodeid);
+ /*
+ * If the first object in the slab is leaked (it's allocated
+ * but no one has a reference to it), we want to make sure
+ * kmemleak does not treat the ->s_mem pointer as a reference
+ * to the object. Otherwise we will not report the leak.
+ */
+ kmemleak_scan_area(slabp, offsetof(struct slab, list),
+ sizeof(struct list_head), local_flags);
if (!slabp)
return NULL;
} else {
@@ -3145,6 +3162,12 @@ static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
STATS_INC_ALLOCMISS(cachep);
objp = cache_alloc_refill(cachep, flags);
}
+ /*
+ * To avoid a false negative, if an object that is in one of the
+ * per-CPU caches is leaked, we need to make sure kmemleak doesn't
+ * treat the array pointers as a reference to the object.
+ */
+ kmemleak_erase(&ac->entry[ac->avail]);
return objp;
}
@@ -3364,6 +3387,8 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
out:
local_irq_restore(save_flags);
ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller);
+ kmemleak_alloc_recursive(ptr, obj_size(cachep), 1, cachep->flags,
+ flags);
if (unlikely((flags & __GFP_ZERO) && ptr))
memset(ptr, 0, obj_size(cachep));
@@ -3419,6 +3444,8 @@ __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller)
objp = __do_cache_alloc(cachep, flags);
local_irq_restore(save_flags);
objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller);
+ kmemleak_alloc_recursive(objp, obj_size(cachep), 1, cachep->flags,
+ flags);
prefetchw(objp);
if (unlikely((flags & __GFP_ZERO) && objp))
@@ -3534,6 +3561,7 @@ static inline void __cache_free(struct kmem_cache *cachep, void *objp)
struct array_cache *ac = cpu_cache_get(cachep);
check_irq_off();
+ kmemleak_free_recursive(objp, cachep->flags);
objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0));
/*