mm, slab: lock the correct nodelist after reenabling irqs
cache_grow() can reenable irqs so the cpu (and node) can change, so ensure
that we take list_lock on the correct nodelist.
This fixes an issue with commit 072bb0aa5e06 ("mm: sl[au]b: add
knowledge of PFMEMALLOC reserve pages") where list_lock for the wrong
node was taken after growing the cache.
Reported-and-tested-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slab.c b/mm/slab.c
index f8b0d53..811af03 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3260,6 +3260,7 @@
/* cache_grow can reenable interrupts, then ac could change. */
ac = cpu_cache_get(cachep);
+ node = numa_mem_id();
/* no objects in sight? abort */
if (!x && (ac->avail == 0 || force_refill))