From 880cd276dff17ea29e9a8404275c9502b265afa7 Mon Sep 17 00:00:00 2001 From: Shakeel Butt Date: Wed, 28 Mar 2018 16:00:57 -0700 Subject: [PATCH] mm, slab: memcg_link the SLAB's kmem_cache 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-shakeelb@google.com Fixes: 510ded33e075c ("slab: implement slab_root_caches list") Signed-off-by: Shakeel Butt Cc: Tejun Heo Cc: Vladimir Davydov Cc: Greg Thelen Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Johannes Weiner Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/slab.c b/mm/slab.c index 324446621b3e..9095c3945425 100644 --- 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, 0, 0); list_add(&kmem_cache->list, &slab_caches); + memcg_link_cache(kmem_cache); slab_state = PARTIAL; /* -- GitLab