4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Shakeel Butt <shake...@google.com>
[ Upstream commit 880cd276dff17ea29e9a8404275c9502b265afa7 ]
All the root caches are linked into slab_root_caches which was
introduced by the commit 510ded33e075 ("slab: implement slab_root_caches
list") but it missed to add the SLAB's kmem_cache.
While experimenting with opt-in/opt-out kmem accounting, I noticed
system crashes due to NULL dereference inside cache_from_memcg_idx()
while deferencing kmem_cache.memcg_params.memcg_caches. The upstream
clean kernel will not see these crashes but SLAB should be consistent
with SLUB which does linked its boot caches (kmem_cache_node and
kmem_cache) into slab_root_caches.
Link: http://lkml.kernel.org/r/20180319210020.60289-1-shake...@google.com
Fixes: 510ded33e075c ("slab: implement slab_root_caches list")
Signed-off-by: Shakeel Butt <shake...@google.com>
Cc: Tejun Heo <t...@kernel.org>
Cc: Vladimir Davydov <vdavydov....@gmail.com>
Cc: Greg Thelen <gthe...@google.com>
Cc: Christoph Lameter <c...@linux.com>
Cc: Pekka Enberg <penb...@kernel.org>
Cc: David Rientjes <rient...@google.com>
Cc: Joonsoo Kim <iamjoonsoo....@lge.com>
Cc: Johannes Weiner <han...@cmpxchg.org>
Cc: Michal Hocko <mho...@kernel.org>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
Signed-off-by: Linus Torvalds <torva...@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
mm/slab.c | 1 +
1 file changed, 1 insertion(+)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1283,6 +1283,7 @@ void __init kmem_cache_init(void)
nr_node_ids * sizeof(struct kmem_cache_node
*),
SLAB_HWCACHE_ALIGN);
list_add(&kmem_cache->list, &slab_caches);
+ memcg_link_cache(kmem_cache);
slab_state = PARTIAL;
/*
