Messages in this thread Patch in this message | | | From | Jeremy Linton <> | Subject | [RFC 1/2] slub: Avoid trying to allocate memory on offline nodes | Date | Wed, 1 Aug 2018 15:04:17 -0500 |
| |
If a user calls the *alloc_node() functions with an invalid node its possible to crash in alloc_pages_nodemask because NODE_DATA() returns a bad node, which propogates into the node zonelist in prepare_alloc_pages. This avoids that by not trying to allocate new slabs against offline nodes.
(example backtrace)
__alloc_pages_nodemask+0x128/0xf48 allocate_slab+0x94/0x528 new_slab+0x68/0xc8 ___slab_alloc+0x44c/0x520 __slab_alloc+0x50/0x68 kmem_cache_alloc_node_trace+0xe0/0x230
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> --- mm/slub.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/mm/slub.c b/mm/slub.c index 51258eff4178..e03719bac1e2 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2519,6 +2519,8 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, if (unlikely(!node_match(page, searchnode))) { stat(s, ALLOC_NODE_MISMATCH); deactivate_slab(s, page, c->freelist, c); + if (!node_online(searchnode)) + node = NUMA_NO_NODE; goto new_slab; } } -- 2.14.3
| |