This is a note to let you know that I've just added the patch titled
kfence: skip __GFP_THISNODE allocations on NUMA systems
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kfence-skip-__gfp_thisnode-allocations-on-numa-syste.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9b107fc8f4ad201c8d87ff57117ea1087ec391b1
Author: Marco Elver <elver@xxxxxxxxxx>
Date: Fri Jan 24 13:01:38 2025 +0100
kfence: skip __GFP_THISNODE allocations on NUMA systems
[ Upstream commit e64f81946adf68cd75e2207dd9a51668348a4af8 ]
On NUMA systems, __GFP_THISNODE indicates that an allocation _must_ be on
a particular node, and failure to allocate on the desired node will result
in a failed allocation.
Skip __GFP_THISNODE allocations if we are running on a NUMA system, since
KFENCE can't guarantee which node its pool pages are allocated on.
Link: https://lkml.kernel.org/r/20250124120145.410066-1-elver@xxxxxxxxxx
Fixes: 236e9f153852 ("kfence: skip all GFP_ZONEMASK allocations")
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Reported-by: Vlastimil Babka <vbabka@xxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Chistoph Lameter <cl@xxxxxxxxx>
Cc: Dmitriy Vyukov <dvyukov@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/mm/kfence/core.c b/mm/kfence/core.c
index 0d1a66811c32b..c49bc76b3a389 100644
--- a/mm/kfence/core.c
+++ b/mm/kfence/core.c
@@ -21,6 +21,7 @@
#include <linux/log2.h>
#include <linux/memblock.h>
#include <linux/moduleparam.h>
+#include <linux/nodemask.h>
#include <linux/notifier.h>
#include <linux/panic_notifier.h>
#include <linux/random.h>
@@ -906,6 +907,7 @@ void *__kfence_alloc(struct kmem_cache *s, size_t size, gfp_t flags)
* properties (e.g. reside in DMAable memory).
*/
if ((flags & GFP_ZONEMASK) ||
+ ((flags & __GFP_THISNODE) && num_online_nodes() > 1) ||
(s->flags & (SLAB_CACHE_DMA | SLAB_CACHE_DMA32))) {
atomic_long_inc(&counters[KFENCE_COUNTER_SKIP_INCOMPAT]);
return NULL;
