From 5c382300876f2337f7b945c159ffcaf285f296ea Mon Sep 17 00:00:00 2001 From: Alok N Kataria Date: Tue, 27 Sep 2005 21:45:46 -0700 Subject: [PATCH] [PATCH] kmalloc_node IRQ safety fix In kmalloc_node we are checking if the allocation is for the same node when interrupts are "on". This may lead to an allocation on another node than intended. This patch just shifts the check for the current node in __cache_alloc_node when interrupts are disabled. Signed-off-by: Alok N Kataria Acked-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index c9adfce004..5cbbdfa6dd 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2510,16 +2510,12 @@ cache_alloc_debugcheck_after(kmem_cache_t *cachep, #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) #endif - -static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags) +static inline void *____cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags) { - unsigned long save_flags; void* objp; struct array_cache *ac; - cache_alloc_debugcheck_before(cachep, flags); - - local_irq_save(save_flags); + check_irq_off(); ac = ac_data(cachep); if (likely(ac->avail)) { STATS_INC_ALLOCHIT(cachep); @@ -2529,6 +2525,18 @@ static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast fl STATS_INC_ALLOCMISS(cachep); objp = cache_alloc_refill(cachep, flags); } + return objp; +} + +static inline void *__cache_alloc(kmem_cache_t *cachep, unsigned int __nocast flags) +{ + unsigned long save_flags; + void* objp; + + cache_alloc_debugcheck_before(cachep, flags); + + local_irq_save(save_flags); + objp = ____cache_alloc(cachep, flags); local_irq_restore(save_flags); objp = cache_alloc_debugcheck_after(cachep, flags, objp, __builtin_return_address(0)); @@ -2856,7 +2864,10 @@ void *kmem_cache_alloc_node(kmem_cache_t *cachep, unsigned int __nocast flags, i cache_alloc_debugcheck_before(cachep, flags); local_irq_save(save_flags); - ptr = __cache_alloc_node(cachep, flags, nodeid); + if (nodeid == numa_node_id()) + ptr = ____cache_alloc(cachep, flags); + else + ptr = __cache_alloc_node(cachep, flags, nodeid); local_irq_restore(save_flags); ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, __builtin_return_address(0)); -- 2.39.5