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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: BC39B80014 X-Stat-Signature: u1bxeydgt56bg3h599u4xo64mg61n83j X-Rspam-User: X-HE-Tag: 1723467630-386087 X-HE-Meta: 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 f4nU09wP BK4XWPjfaz86oSwhUr4Ek9Blq5MU7WzRdUFMZ8QSspyBswNc3OckjWtIlGJR7kij9D0n+zmoLyO8G1nzFizIqxYyNhC52EOLBjjh3Xe36Mdy2pltNCOx0Gm89XYvXfLmsCxzZjvV1aqad6B1TVjvW5rputqVH8RXXyB5ZvUyfrQ7X/36roMlvmb+/2CnjlFLiayBJPn3ulOfbvjGG/9LomDtkO7MbW29vbeQoBqL46uqL4HFOts+hvA6WZl7faglQQ0CIoWrO2u1Uu17u0STBe7GQ0wXQmOI9XBVQgVefv1rjFPtWYsoEx2zpeHpzNxtiie0PYpR4+5fti4qyubbRtqOm3zvGAGhOaBWShlPLtZIXuOcrjeK0T11yPc5/M+8T1rsisJMkPph5wel4ygk6fAN6IkQCkn6p+MpukqIuFzzeo55e9s1Cbsy2OiJcDFWxL0v82Ruuw3wJKk0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.024771, 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 Mon, Aug 12, 2024 at 7:37=E2=80=AFPM Christoph Hellwig wrote: > > On Mon, Aug 12, 2024 at 05:05:24PM +0800, Yafang Shao wrote: > > The PF_MEMALLOC_NORECLAIM flag was introduced in commit eab0af905bfc > > ("mm: introduce PF_MEMALLOC_NORECLAIM, PF_MEMALLOC_NOWARN"). To complem= ent > > this, let's add two helper functions, memalloc_nowait_{save,restore}, w= hich > > will be useful in scenarios where we want to avoid waiting for memory > > reclamation. > > No, forcing nowait on callee contets is just asking for trouble. > Unlike NOIO or NOFS this is incompatible with NOFAIL allocations I don=E2=80=99t see any incompatibility in __alloc_pages_slowpath(). The ~__GFP_DIRECT_RECLAIM flag only ensures that direct reclaim is not performed, but it doesn=E2=80=99t prevent the allocation of pages from ALLOC_MIN_RESERVE, correct? > and thus will lead to kernel crashes. Could you please explain in detail where this might lead to kernel crashes? -- Regards Yafang