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DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from]; RCVD_VIA_SMTP_AUTH(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; R_RATELIMIT(0.00)[to_ip_from(RLykmtnuwwt3p9ueb9muqcqoc7)]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,suse.de:email,suse.de:mid,suse.de:dkim] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -4.51 X-Spam-Level: On 11/25/25 12:54, Nilay Shroff wrote: > > > On 11/25/25 5:00 PM, Christoph Hellwig wrote: >> On Tue, Nov 25, 2025 at 04:58:32PM +0530, Nilay Shroff wrote: >>> >From git history, I see that was added to avoid memory reclaim to avoid >>> possible circular locking dependency. This commit 83e1226b0ee2 ("nvme-tcp: >>> fix possible circular locking when deleting a controller under memory >>> pressure") adds it. >> >> I suspect this was intended to be noio, and we should just switch to >> that. >> > Yeah, I agree that this should be changed to noio. However, it seems that > this alone may not be sufficient to fix the lockdep splat reported here. > Since the real work of fput() might be deferred to another thread, using a noio > scope in this path may not have the intended effect and could end up being > redundant. > > That said, I noticed another fix from Chaitanya [1], where fput() is replaced > with __fput_sync(). With that change in place, combining the noio scope adjustment > with the switch to __fput_sync() should indeed address the lockdep issue. Given > that both problems have very similar lockdep signatures, it might make sense to > merge these two changes into a single fix. > > [1] https://lore.kernel.org/all/20251125005950.41046-1-ckulkarnilinux@gmail.com/ > Yes, we should. Both address similar symptoms, and I wouldn't be surprised both turn out to address the same issue. (Frame #0 from here is basically identical to frame #2 in the referenced issue). So please roll both into one patch. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich