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Howlett" , syzbot , akpm@linux-foundation.org, jannh@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, pfalcato@suse.de, syzkaller-bugs@googlegroups.com References: <69e1f975.050a0220.1de265.0009.GAE@google.com> From: "Vlastimil Babka (SUSE)" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Stat-Signature: 6m8dexibkyucsxkbrzznm5u5n4d56aoy X-Rspam-User: X-Rspamd-Queue-Id: 819FF1C0002 X-HE-Tag: 1776674185-827371 X-HE-Meta: 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 h6iYiTxr 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/18/26 01:50, Liam R. Howlett wrote: > * syzbot [260417 05:12]: >> Hello, >> >> syzbot found the following issue on: >> >> HEAD commit: 1d51b370a0f8 Merge tag 'jfs-7.1' of github.com:kleikamp/li.. >> git tree: upstream >> console output: https://syzkaller.appspot.com/x/log.txt?x=117dc4ce580000 >> kernel config: https://syzkaller.appspot.com/x/.config?x=7f207c4b1fbf85a3 >> dashboard link: https://syzkaller.appspot.com/bug?extid=38a879f4a73497f2dfef >> compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 >> >> Unfortunately, I don't have any reproducer for this issue yet. > > ... and you won't. This will work unless we tear aligned unsigned long > writes/reads. Note I think the reproducer here means code that will trigger that KCSAN alert deterministically (as opposed to fuzzing), not something that would depend on whether the alert is pointing to a "real" problem.