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Ts'o" , Chris Mason , Josef Bacik , Luis Chamberlain Subject: [LSF/MM/BPF Topic] Filesystem reclaim & memory allocation BOF Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 1FC0040013 X-Stat-Signature: c6p6u1k6cdxwwsajm6sohms5d6cwcyuw X-HE-Tag: 1743002712-240805 X-HE-Meta: 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 wMfFhhl+ R7AbokItPddA1Zwi4eKzHOMbaOpWWTXa0k74Uc4VwbeDGNSYj6BN8zsJKdPePVDo84m2aLSo847EmnOW5Cay0+9EJ0y9cdKG5al2vhjqPUnIZ51Io51Iy1UMiaAWhjcsQ6luTcWYIdXh0WZ/T/YkmbZ1TrbHDS672XYvgx4V0kl7yIHRlc8tZUqmp6OBEwVBhXO8Zc1F15pf7Cp9+p9/XW1zHkdI1zNvMSzEE9e9qcyplddZ2SRsNVNAtc+dFVy+guZCE4LO+aHUoYgW1KzlyQUi+2JltZGHEFPmziioIiLiByEh3cMNhYPOvZg== 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: We've got three reports now (two are syzkaller kiddie stuff, but one's a real workload) of a warning in the page allocator from filesystems doing reclaim. Essentially they're using GFP_NOFAIL from reclaim context. This got me thinking about bs>PS and I realised that if we fix this, then we're going to end up trying to do high order GFP_NOFAIL allocations in the memory reclaim path, and that is really no bueno. https://lore.kernel.org/linux-mm/20250326105914.3803197-1-matt@readmodwrite.com/ I'll prepare a better explainer of the problem in advance of this. It looks like we have a slot at 17:30 today? Required attendees: Ted, Luis, Chris, Josef, other people who've wrestled with this before.