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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: D2EA012002F X-Stat-Signature: tm35nbiodgwjr6d956k4jwygfnh8wuas X-HE-Tag: 1723468909-399268 X-HE-Meta: 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 MoNFCnwb 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000003, 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 08:59:53PM +0800, Yafang Shao wrote: > > I don’t see any incompatibility in __alloc_pages_slowpath(). The > ~__GFP_DIRECT_RECLAIM flag only ensures that direct reclaim is not > performed, but it doesn’t 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? Sorry, I misread your patch as doing what your subject says. A nestable noreclaim is probably fine, but please name it that way, as memalloc_nowait_{save,restore} implies a context version of GFP_NOWAIT.