From: Hillf Danton <hdanton@sina.com>
To: syzbot <syzbot+fb86166504f57eff29d7@syzkaller.appspotmail.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [mm?] kernel BUG in try_to_unmap_one
Date: Sun, 2 Mar 2025 07:40:01 +0800 [thread overview]
Message-ID: <20250301234002.2893-1-hdanton@sina.com> (raw)
In-Reply-To: <67c38d10.050a0220.dc10f.016d.GAE@google.com>
On Sat, 01 Mar 2025 14:41:20 -0800
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: e5d3fd687aac Add linux-next specific files for 20250218
> git tree: linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12faf7f8580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=4e945b2fe8e5992f
> dashboard link: https://syzkaller.appspot.com/bug?extid=fb86166504f57eff29d7
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/ef079ccd2725/disk-e5d3fd68.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/99f2123d6831/vmlinux-e5d3fd68.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/eadfc9520358/bzImage-e5d3fd68.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+fb86166504f57eff29d7@syzkaller.appspotmail.com
>
> evict+0x4e8/0x9a0 fs/inode.c:806
> __dentry_kill+0x20d/0x630 fs/dcache.c:660
> dput+0x19f/0x2b0 fs/dcache.c:902
> __fput+0x60b/0x9f0 fs/file_table.c:472
> task_work_run+0x24f/0x310 kernel/task_work.c:227
> resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
> exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
> exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
> __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
> syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
> do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> ------------[ cut here ]------------
> kernel BUG at mm/rmap.c:1858!
> Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
> CPU: 1 UID: 0 PID: 6053 Comm: syz.4.27 Not tainted 6.14.0-rc3-next-20250218-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
> RIP: 0010:try_to_unmap_one+0x3d0d/0x3fa0 mm/rmap.c:1858
> Code: c7 c7 80 93 c3 8e 48 89 da e8 ef f3 19 03 e9 68 ca ff ff e8 b5 12 ab ff 48 8b 7c 24 20 48 c7 c6 80 17 36 8c e8 94 d2 f5 ff 90 <0f> 0b e8 9c 12 ab ff 48 8b 7c 24 18 48 c7 c6 40 1c 36 8c e8 7b d2
> RSP: 0018:ffffc9000b1be9c0 EFLAGS: 00010246
> RAX: 367eb4645686ad00 RBX: 00000000f4000000 RCX: ffffc9000b1be503
> RDX: 0000000000000004 RSI: ffffffff8c2aaf60 RDI: ffffffff8c8156e0
> RBP: ffffc9000b1bedf0 R08: ffffffff903da477 R09: 1ffffffff207b48e
> R10: dffffc0000000000 R11: fffffbfff207b48f R12: 8000000053c008e7
> R13: dffffc0000000000 R14: ffffea00014f0000 R15: ffffea00014f0030
> FS: 00007f4d2783e6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 000000110c465fa1 CR3: 000000002a1f6000 CR4: 00000000003526f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> __rmap_walk_file+0x420/0x5f0 mm/rmap.c:2774
> try_to_unmap+0x219/0x2e0
> unmap_folio+0x183/0x1f0 mm/huge_memory.c:3053
> __folio_split+0x849/0x16d0 mm/huge_memory.c:3696
> truncate_inode_partial_folio+0x9b1/0xdc0 mm/truncate.c:234
> shmem_undo_range+0x82f/0x1820 mm/shmem.c:1143
Given folio_test_hugetlb(folio) [1], what is weird is hugetlb page in a
shmem mapping.
[1] https://web.git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/mm/rmap.c?id=e5d3fd687aac#n1851
> shmem_truncate_range mm/shmem.c:1237 [inline]
> shmem_fallocate+0x431/0xf20 mm/shmem.c:3663
> vfs_fallocate+0x623/0x7a0 fs/open.c:338
> madvise_remove mm/madvise.c:1034 [inline]
> madvise_vma_behavior mm/madvise.c:1263 [inline]
> madvise_walk_vmas mm/madvise.c:1505 [inline]
> madvise_do_behavior+0x1ec6/0x3b90 mm/madvise.c:1657
> do_madvise mm/madvise.c:1755 [inline]
> __do_sys_madvise mm/madvise.c:1763 [inline]
> __se_sys_madvise mm/madvise.c:1761 [inline]
> __x64_sys_madvise+0x11b/0x140 mm/madvise.c:1761
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
next prev parent reply other threads:[~2025-03-01 23:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-01 22:41 [syzbot] [mm?] kernel BUG in try_to_unmap_one syzbot
2025-03-01 23:40 ` Hillf Danton [this message]
2025-03-03 16:46 ` David Hildenbrand
2025-03-03 16:54 ` Zi Yan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20250301234002.2893-1-hdanton@sina.com \
--to=hdanton@sina.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=syzbot+fb86166504f57eff29d7@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox