diff options
| author | Gregory Price <gourry@gourry.net> | 2026-07-01 18:16:13 -0400 |
|---|---|---|
| committer | Mike Rapoport (Microsoft) <rppt@kernel.org> | 2026-07-02 11:54:52 +0300 |
| commit | 2ebce860bdd7ae5e13002811bc9bbbf33fcfc221 (patch) | |
| tree | 4cd03b33403129cb6b604e21f21141eb7d06824a /mm/memory_hotplug.c | |
| parent | 7783dcd79ae9c4aa48bc47bd4275772445dc4b2a (diff) | |
mm/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
We miss a failed allocation check for pgdat->per_cpu_nodestats, which
results in a NULL deref when we offset into the per-cpu area.
Propagate -ENOMEM up the stack and leave per_cpu_nodestats pointing
at boot_nodestats so a later online can retry the allocation.
hotadd_init_pgdat() returns NULL on failure, which __try_online_node()
already maps to -ENOMEM.
On failure nothing needs to be unwound:
- the node is never marked online
- per_cpu_nodestats is left pointing at boot_nodestats
- __add_memory_resource() cleans up pending memblock resources
- later online attempts retry the per_cpu_nodestats allocation
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260627202243.758289-1-gourry%40gourry.net
Fixes: 75ef71840539 ("mm, vmstat: add infrastructure for per-node vmstats")
Signed-off-by: Gregory Price <gourry@gourry.net>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Link: https://patch.msgid.link/20260701221613.2818148-1-gourry@gourry.net
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Diffstat (limited to 'mm/memory_hotplug.c')
| -rw-r--r-- | mm/memory_hotplug.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 7ac19fab2263..8b137328dcf0 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1263,7 +1263,8 @@ static pg_data_t *hotadd_init_pgdat(int nid) pgdat = NODE_DATA(nid); /* init node's zones as empty zones, we don't have any present pages.*/ - free_area_init_core_hotplug(pgdat); + if (free_area_init_core_hotplug(pgdat)) + return NULL; /* * The node we allocated has no zone fallback lists. For avoiding |