From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79E6E393DEA for ; Sat, 23 Aug 2025 17:07:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755968824; cv=none; b=Nc108h+24GhllLzSoim4kX7opNE2/DrCLBZZprN3eqXM95t9/fSj8dfklOzbxJ37eHdPSQdQW8Pb1ydJyxLe+g5qzeiLPc8qZXBv/j9nGg8X0NPf4DKT1RuTmzbV4TcHnrJmrkw2T7tahykD2skgYu+A5P92Otq8izFk+D58z14= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755968824; c=relaxed/simple; bh=zsnLpOJ+msRihUwNBF9a5KmdzajefwvuxfqUE283cp8=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=EfVLY0I5at2e/FTcRfrar3ajJWQat2oPWuNEIUp8+5DSserrC+GWCiuxFeRSTv7dMZXazkWR8SSkNZVnCvr1dlOrx+ommQitFhpZ4Q1LZny6zgGkB7QOeNBwDqJDxmQiToa8uO1W+S/JQssdaG/x/AsQ02iSuyCavhbfWiwnQVU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=LpYMMTV9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="LpYMMTV9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5EFAC4CEE7; Sat, 23 Aug 2025 17:07:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1755968824; bh=zsnLpOJ+msRihUwNBF9a5KmdzajefwvuxfqUE283cp8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=LpYMMTV9QibwTHYmaRpvNBq+xiR0jSQM86DOFG9fPeqgQH1S5TinNmns1FwCAxM2L lBqCmVK+wN156VaB0d9J4p2KYFnuEBpxaecgqzD9U7aTtp7KwuaZWGpREvoo6EKVMr umTzZzvQOqT3Q5+ysFuXtoi9Ukf3QqwOSjxY7Nvk= Date: Sat, 23 Aug 2025 10:07:03 -0700 From: Andrew Morton To: Ritesh Harjani (IBM) Cc: syzbot , linux-kernel@vger.kernel.org, linux-mm@kvack.org, pasha.tatashin@soleen.com, syzkaller-bugs@googlegroups.com, Andrew Donnellan Subject: Re: [syzbot] [mm?] kernel BUG in page_table_check_set Message-Id: <20250823100703.0a0239d204ca2487363d2adf@linux-foundation.org> In-Reply-To: <875xeeafgv.fsf@gmail.com> References: <68a7ef20.050a0220.37038e.004d.GAE@google.com> <20250822181653.cd2024360870ef94cdb7db07@linux-foundation.org> <875xeeafgv.fsf@gmail.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Sat, 23 Aug 2025 08:53:28 +0530 Ritesh Harjani (IBM) wrote: > Andrew Morton writes: > > > On Thu, 21 Aug 2025 21:16:32 -0700 syzbot wrote: > > > >> Hello, > >> > >> syzbot found the following issue on: > >> > >> HEAD commit: 8f5ae30d69d7 Linux 6.17-rc1 > >> git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > >> console output: https://syzkaller.appspot.com/x/log.txt?x=15f926f0580000 > >> kernel config: https://syzkaller.appspot.com/x/.config?x=8c5ac3d8b8abfcb > >> dashboard link: https://syzkaller.appspot.com/bug?extid=49a796ed2c9709652f1e > >> compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > >> userspace arch: arm64 > >> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15faa7a2580000 > >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=144143bc580000 > >> > >> Downloadable assets: > >> disk image: https://storage.googleapis.com/syzbot-assets/18a2e4bd0c4a/disk-8f5ae30d.raw.xz > >> vmlinux: https://storage.googleapis.com/syzbot-assets/3b5395881b25/vmlinux-8f5ae30d.xz > >> kernel image: https://storage.googleapis.com/syzbot-assets/e875f4e3b7ff/Image-8f5ae30d.gz.xz > >> > >> IMPORTANT: if you fix the issue, please add the following tag to the commit: > >> Reported-by: syzbot+49a796ed2c9709652f1e@syzkaller.appspotmail.com > >> > >> ------------[ cut here ]------------ > >> kernel BUG at mm/page_table_check.c:118! > > > > Thanks. > > > > Presumably due to the series "Support page table check on PowerPC". > > The syzbot triggered this on: > HEAD commit: 8f5ae30d69d7 Linux 6.17-rc1 > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > > This tree does not have "Support page table check on PowerPC", correct? Yep, sorry. > Also, I guess Dev's change fixes this reported problem which could happen in > this path: commit_anon_folio_batch() -> change_pte_range() ... > > [1]: https://lore.kernel.org/all/20250812060124.C9344C4CEF0@smtp.kernel.org/ > [2]: https://lore.kernel.org/all/68a80cc6.050a0220.3809a8.0002.GAE@google.com/ Cool. Dev's fix is in 6.17-rc2 as cf1b80dc31a1. #syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git c17b750b3ad9