The patch titled
Subject: kfence: skip __GFP_THISNODE allocations on NUMA systems
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
kfence-skip-__gfp_thisnode-allocations-on-numa-systems.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kfence-skip-__gfp_thisnode-allocations-on-numa-systems.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Marco Elver <elver@xxxxxxxxxx>
Subject: kfence: skip __GFP_THISNODE allocations on NUMA systems
Date: Fri, 24 Jan 2025 13:01:38 +0100
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>
---
mm/kfence/core.c | 2 ++
1 file changed, 2 insertions(+)
--- a/mm/kfence/core.c~kfence-skip-__gfp_thisnode-allocations-on-numa-systems
+++ a/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>
@@ -1084,6 +1085,7 @@ void *__kfence_alloc(struct kmem_cache *
* 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;
_
Patches currently in -mm which might be from elver@xxxxxxxxxx are
kfence-skip-__gfp_thisnode-allocations-on-numa-systems.patch
