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b=Mi2tRmrMgxOLokAy7WBVBO+vqXEy30vNILVvF1MelwmHL+jsDxyu3UvCAPejBdc1z HvV9ZINHHX5NYdfn8cc18INewbfUT0d1gsVoRd1fdPLuLEKIAJW1w3Zt9rW8kuNLJL Djsh+mUznB/jkcdxzkJeOcuBpnSoLD6EH84y03bDAQcjaCTja3fkk1s11foF5leU0T SKnS3LgvGST45kR6X4yt2rfiJ9jutmbSUSOjmG3vO06NUNnG+MewOn0x6uWKJ0duiW lqLGGi6sCGVUBWP5JQj2RSjShLuNf9bhZ0yZAFkUwHH9OflrVygU7woH5Qmkc60IBY 8RDoMelal0ykg== Message-ID: <8ab10631-4672-4196-b32e-7c5a01707424@kernel.org> Date: Thu, 19 Mar 2026 10:21:40 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [syzbot] [mm?] kernel BUG in collapse_scan_file To: Lance Yang , "Lorenzo Stoakes (Oracle)" Cc: syzbot , willy@infradead.org, baolin.wang@linux.alibaba.com, npache@redhat.com, linux-mm@kvack.org, baohua@kernel.org, ryan.roberts@arm.com, syzkaller-bugs@googlegroups.com, dev.jain@arm.com, ziy@nvidia.com, linux-kernel@vger.kernel.org, Liam.Howlett@oracle.com, akpm@linux-foundation.org References: <69bba3c0.050a0220.227207.002b.GAE@google.com> <10e5f1d6-077d-4783-aa16-6c8b98cb9e74@lucifer.local> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 2D8DA2000D X-Stat-Signature: d4xidj65forsbw4uey6tnfjsrs15xf88 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1773912109-570927 X-HE-Meta: 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 MTUGNfN6 15JnmOTLtj0FEKnJDiyQhHSku9UksMkE55eM8r4eHM6hl5VZlzN54Fsw8X/p6wq7xoFWvgZwo57RJnVNAs311CoP/WWmTPt89etplMjmBbDs4XqiG5x10HYw09ZHjI1X8r5RoANhyR9Nmzsxrl6AYoTY7Ug== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/19/26 10:14, Lance Yang wrote: > > > On 2026/3/19 17:00, David Hildenbrand (Arm) wrote: >> On 3/19/26 09:53, Lorenzo Stoakes (Oracle) wrote: >>> >>> Hmm we shouldn't leave this bug in place while working for a fancier >>> fix?? >>> >>> Can we get _something_ going as an upstream fix? We can improve >>> whatever we do >>> later right? >>> >>> David, thoughts? >> >> I recall Willy mentioning that the issue is likely a false positive. >> >> IIUC, that commit is not upstream? So it only triggers in linux-next. > > Right. That does not appear to be in upstream, I only see it in linux- > next :) > >> Which means: >> >> 1) If it's a false positive, upstream is not effected (no XA_NODE_BUG_ON) >> >> 2) If it's not a false positive, upstream is effected but does not >> trigger the XA_NODE_BUG_ON > > Yep. So this particular BUG_ON is not affecting upstream directly. > > That said, syzbot will likely keep hitting it in linux-next and > generating noise for us until it is addressed there ... Right, I assume this comes through Willy's tree, so Willy should consider removing it for the time being. -- Cheers, David