From a44b56d354b49f9abb184e5a14f71889856283bb Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Wed, 6 Dec 2006 20:32:11 -0800 Subject: [PATCH] slab debug and ARCH_SLAB_MINALIGN don't get along When CONFIG_SLAB_DEBUG is used in combination with ARCH_SLAB_MINALIGN, some debug flags should be disabled which depend on BYTES_PER_WORD alignment. The disabling of these debug flags is not properly handled when BYTES_PER_WORD < ARCH_SLAB_MEMALIGN < cache_line_size() This patch fixes that and also adds an alignment check to cache_alloc_debugcheck_after() when ARCH_SLAB_MINALIGN is used. Signed-off-by: Kevin Hilman Cc: Pekka Enberg Cc: Christoph Lameter Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'mm') diff --git a/mm/slab.c b/mm/slab.c index 5de81473df3..ff60a94142f 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2197,18 +2197,17 @@ kmem_cache_create (const char *name, size_t size, size_t align, if (flags & SLAB_RED_ZONE || flags & SLAB_STORE_USER) ralign = BYTES_PER_WORD; - /* 2) arch mandated alignment: disables debug if necessary */ + /* 2) arch mandated alignment */ if (ralign < ARCH_SLAB_MINALIGN) { ralign = ARCH_SLAB_MINALIGN; - if (ralign > BYTES_PER_WORD) - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); } - /* 3) caller mandated alignment: disables debug if necessary */ + /* 3) caller mandated alignment */ if (ralign < align) { ralign = align; - if (ralign > BYTES_PER_WORD) - flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); } + /* disable debug if necessary */ + if (ralign > BYTES_PER_WORD) + flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); /* * 4) Store it. */ @@ -3063,6 +3062,12 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, cachep->ctor(objp, cachep, ctor_flags); } +#if ARCH_SLAB_MINALIGN + if ((u32)objp & (ARCH_SLAB_MINALIGN-1)) { + printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n", + objp, ARCH_SLAB_MINALIGN); + } +#endif return objp; } #else -- cgit v1.2.3