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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251001192647.195204-9-urezki@gmail.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-Rspamd-Queue-Id: BB2B18000D X-Stat-Signature: n7dw6zm1izno1t196bxgwibtq8sxwbq9 X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1759550007-271548 X-HE-Meta: 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 Yg0SeyHq 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 10/01/25 at 09:26pm, Uladzislau Rezki (Sony) wrote: > 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. > > Acked-by: Michal Hocko > Signed-off-by: Uladzislau Rezki (Sony) > --- > include/linux/sched/mm.h | 3 +++ > 1 file changed, 3 insertions(+) Reviewed-by: Baoquan He > > 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)); > } > > -- > 2.47.3 >