[PATCH] slab: fix sleeping in atomic bug

Fallback_alloc() does not do the check for GFP_WAIT as done in
cache_grow().  Thus interrupts are disabled when we call kmem_getpages()
which results in the failure.

Duplicate the handling of GFP_WAIT in cache_grow().

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Jay Cliburn <jacliburn@bellsouth.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/mm/slab.c b/mm/slab.c
index 2c655532f5efcefac182e20cd2bb325decb92407..c7576b9027a6fbe53c754053890036f94c0e69fe 100644 (file)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3252,6 +3252,7 @@ void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
        struct zone **z;
        void *obj = NULL;
        int nid;
+       gfp_t local_flags = (flags & GFP_LEVEL_MASK);
 
 retry:
        /*
@@ -3275,7 +3276,12 @@ retry:
                 * We may trigger various forms of reclaim on the allowed
                 * set and go into memory reserves if necessary.
                 */
+               if (local_flags & __GFP_WAIT)
+                       local_irq_enable();
+               kmem_flagcheck(cache, flags);
                obj = kmem_getpages(cache, flags, -1);
+               if (local_flags & __GFP_WAIT)
+                       local_irq_disable();
                if (obj) {
                        /*
                         * Insert into the appropriate per node queues