From 1a8c022282b9f9fe630aa94bc8acc06e1aa52e7c Mon Sep 17 00:00:00 2001 From: "Uladzislau Rezki (Sony)" Date: Tue, 7 Oct 2025 14:20:33 +0200 Subject: [PATCH] mm: skip might_alloc() warnings when PF_MEMALLOC is set might_alloc() catches invalid blocking allocations in contexts where sleeping is not allowed. However when PF_MEMALLOC is set, the page allocator already skips reclaim and other blocking paths. In such cases, a blocking gfp_mask does not actually lead to blocking, so triggering might_alloc() splats is misleading. Adjust might_alloc() to skip warnings when the current task has PF_MEMALLOC set, matching the allocator's actual blocking behaviour. Link: https://lkml.kernel.org/r/20251007122035.56347-9-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Reviewed-by: Baoquan He Acked-by: Michal Hocko Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Marco Elver Cc: Michal Hocko Signed-off-by: Andrew Morton --- include/linux/sched/mm.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index 0232d983b715..a74582aed747 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -318,6 +318,9 @@ static inline void might_alloc(gfp_t gfp_mask) fs_reclaim_acquire(gfp_mask); fs_reclaim_release(gfp_mask); + if (current->flags & PF_MEMALLOC) + return; + might_sleep_if(gfpflags_allow_blocking(gfp_mask)); } -- 2.51.0