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AJvYcCUgxph3sokHzVdWeRKW+GGJ69YAvuLXFYMij7J7lR3O36W5l/FaMi4UuBSjQxFP227r+GTE6VWGiQ==@kvack.org X-Gm-Message-State: AOJu0YzmdDi55V/wpidGKxNijcRpoyZUwUOF4y8GiYhGlyAoI4e0x9oN yoVsoEeHV+sxsHkIglBp0XtD7w3WQtmGNIpIRo/idDgNcNhYctviuwXJCqV+TlVXiMEHKxT2uTN j3HShpEnZdd/FxKT6Je0NbJtxLHcy58I= X-Gm-Gg: AY/fxX6vi5g+nCig2bcq0sSmry4LKPZ21TpSxn/V5aB3gLojSvF8plyP3BOzcWjPHRM imfAnR7s5qfKwgN52ZeUiBImL5bTlrU3cHWJ8CTgcdoWFvrHbq2WSbsBE5yuGxpVhsKIsmSKYoZ JM3BnRNFXWK6tWICG1y5tb5r+63Ci+j5buxmj6wtnJ7EiEtezFV6laDY776sSCZSfJmoDCJ3h2z 3uuXa7H8EBz7qgrqSMCIJ43KNjX1sDlxRJbvoOKX0rVCAAmWVWCE82FW73cshIlxobc2LlWF7IL TmR3Htd9m6CzUNoGaDeGtzuTQ0wf9PBpBNAL7Ja3h4Ssl51NwR747O+erwE= X-Received: by 2002:a05:690e:1302:b0:63f:9a63:46e5 with SMTP id 956f58d0204a3-64916485743mr6337211d50.28.1768710086767; Sat, 17 Jan 2026 20:21:26 -0800 (PST) MIME-Version: 1.0 References: <696b56b1.050a0220.3390f1.0007.GAE@google.com> <20260117165722.6dc25d72fd58254cb89e711b@linux-foundation.org> In-Reply-To: <20260117165722.6dc25d72fd58254cb89e711b@linux-foundation.org> From: Deepanshu Kartikey Date: Sun, 18 Jan 2026 09:51:15 +0530 X-Gm-Features: AZwV_QixRjSHf6Sj2BD4t0Ssbbsgw1OyPwSQbE8CQ4kPIPXAspb8klvrwkVJpOY Message-ID: Subject: Re: [syzbot] [cgroups?] [mm?] WARNING in memcg1_swapout To: Andrew Morton Cc: syzbot , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, syzkaller-bugs@googlegroups.com, Johannes Weiner , Muchun Song , Minchan Kim Content-Type: text/plain; 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> > which was added by Deepanshu's "mm/swap_cgroup: fix kernel BUG in > swap_cgroup_record". > > This patch has Fixes: 1a4e58cce84e ("mm: introduce MADV_PAGEOUT"), > which is six years old. For some reason it has no cc:stable. > > Deepanshu's patch has no reviews. > > So can I please do the memcg maintainer summoning dance here? We have a > repeatable BUG happening in mainline Linux. > Hi Andrew, I checked the git blame output for commit 0f853ca2a798: Line 763: memcg1_swapout(folio, swap); Line 764: __swap_cache_del_folio(ci, folio, swap, shadow); (d7a7b2f91f36b - Kairui Song, 2026-01-13 02:33:36 +0800= ) Kairui's reordering patch appears to have been merged on Jan 13. The syzbot report is also from Jan 13, likely from earlier in the day before the reordering patch was merged. So this report is from before the fix. The warning should not appear in linux-next builds after Jan 13. Thanks, Deepanshu