From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f77.google.com (mail-io1-f77.google.com [209.85.166.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9CF20311955 for ; Wed, 5 Nov 2025 11:40:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762342836; cv=none; b=aWgyaK4B+AZahUE0T6WZRLP7S58Bblba8JYFG1OCU1K99e5UFpThDfgNrrwVFk0Wsj9DMA2Pd+GDDm1PQyR+FVhMPwC+66geXtKJzoaepAw5xuNt5foyAG7tPr+xSsEuCpik6usw9J1pfraS8fFY1OhBcURjcTpbRcpYaqHGG84= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762342836; c=relaxed/simple; bh=yqwY/afYV+ckN/oCAO8lFiv7v396StoxoLhmZSZGq7Q=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=lLPg0Dv2v6fwCsNYly20a1Lmk72IXrUJ6NkhFfx8C6HO4mVCYlBBegMLPhXZ88iHvuzLx7yoGETV2FzRKJpMTmZUH2+tkcCQ0dJCMROo1AvOKTwV5Y0N5OyFad7GNEMdG/uCb9ekmI98HDoDhcOkF4SKzaYJ2vb0YaXUKmlm+5Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f77.google.com with SMTP id ca18e2360f4ac-9486e1db3d9so171591339f.2 for ; Wed, 05 Nov 2025 03:40:34 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762342834; x=1762947634; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=YBBe2JCcXBqTzvOjhwhihXnJkzzKxXLL3JvbiMRzWDk=; b=O6ROC5kvrQSFqPQav9TVjJ5HVxGAu6WGi3JcY7fUaVmsYRkH+SSgG7Vuurq0W+sv5F zzJqvZBHXtvIyRdzQfT1Mrlpr1pn+IrpUS6ArX85iusdj84dnA3hfrXMeHVN8Wirt+z7 4h5gE8oy7D7tig3kNp7P/KH4yH1uscRw7yySe5j5N9sdg1Kh5sBxQDmbdf8N6O4Q/c3B 5gzM3hvXD1NwL7rnpzrt4jPFJf1d+AjtBW03TVXpUmNaKJDtpPsdsh70/gkU+9s+Vd+W GTv3kzSf154CzswwelpYrMj3TeWA03je0L7VIJG8oOSoDz6oHcEihzSn8/kX6krjjsB3 ch8Q== X-Forwarded-Encrypted: i=1; AJvYcCVIdfDnqalPTSM0mgkjUKw1q7wB0WSc66ste+xbRWu4mKiTDHR+dpD8IVVYY/B3UpSSFATPX0B2MMfCMm4=@vger.kernel.org X-Gm-Message-State: AOJu0YyJLzL5Y1ttl824ZuFJbrhRZcdaNccCatgC+zSgjIf4hvEwzzdJ DXVPe7Ktn/6nAdL2s3B8A/HQ6gMXHGphmAvOWBXw6DzyXdvLvDKL1nHUXpo/JbKkjtsnBuWzrJK JAsvZWR/ujnF38EUnN9r/OZ83/alol/f8llTx2VbPYq3AV36NAXm83Pcyg/c= X-Google-Smtp-Source: AGHT+IHBjUr8KCPc9cpYYCappo2BfgB3itMng7ncMGGo3MwQsjd0u3XpzayT+1m2ijArdo5W2FYIgq31WmWMmy1MHLWJQr88a7b3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:3c05:b0:42f:8b0f:bad2 with SMTP id e9e14a558f8ab-433407a3e4dmr44035875ab.10.1762342833842; Wed, 05 Nov 2025 03:40:33 -0800 (PST) Date: Wed, 05 Nov 2025 03:40:33 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <690b37b1.050a0220.3d0d33.0030.GAE@google.com> Subject: [syzbot] [ext4?] possible deadlock in ext4_evict_inode (5) From: syzbot To: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tytso@mit.edu Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 8bb886cb8f3a Merge tag 'edac_urgent_for_v6.18_rc5' of git:.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13cea292580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e46b8a1c645465a9 dashboard link: https://syzkaller.appspot.com/bug?extid=212e8f62790f8e0bc63b compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/addfade563b0/disk-8bb886cb.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/1254c89ad16b/vmlinux-8bb886cb.xz kernel image: https://storage.googleapis.com/syzbot-assets/3123c5319b7e/bzImage-8bb886cb.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+212e8f62790f8e0bc63b@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.256/7158 is trying to acquire lock: ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1916 [inline] ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:2099 [inline] ffff88802fee4610 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215 but task is already holding lock: ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1808 [inline] ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x2f3/0x1010 fs/ext4/migrate.c:438 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53 percpu_down_read include/linux/percpu-rwsem.h:77 [inline] ext4_writepages_down_read fs/ext4/ext4.h:1796 [inline] ext4_writepages+0x1cc/0x350 fs/ext4/inode.c:3024 do_writepages+0x32e/0x550 mm/page-writeback.c:2604 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719 writeback_single_inode+0x1f9/0x6a0 fs/fs-writeback.c:1840 write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2903 iput_final fs/inode.c:1901 [inline] iput+0x830/0xc50 fs/inode.c:1966 ext4_xattr_block_set+0x1fce/0x2ac0 fs/ext4/xattr.c:2199 ext4_xattr_move_to_block fs/ext4/xattr.c:2664 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2739 [inline] ext4_expand_extra_isize_ea+0x12da/0x1ea0 fs/ext4/xattr.c:2827 __ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6364 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6407 [inline] __ext4_mark_inode_dirty+0x46c/0x700 fs/ext4/inode.c:6485 ext4_evict_inode+0x80d/0xee0 fs/ext4/inode.c:254 evict+0x504/0x9c0 fs/inode.c:810 ext4_orphan_cleanup+0xc20/0x1460 fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5617 [inline] ext4_fill_super+0x5920/0x61e0 fs/ext4/super.c:5736 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 vfs_get_tree+0x92/0x2b0 fs/super.c:1751 fc_mount fs/namespace.c:1208 [inline] do_new_mount_fc fs/namespace.c:3651 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3727 do_mount fs/namespace.c:4050 [inline] __do_sys_mount fs/namespace.c:4238 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4215 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_internal){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53 percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1916 [inline] sb_start_intwrite include/linux/fs.h:2099 [inline] ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215 evict+0x504/0x9c0 fs/inode.c:810 ext4_ext_migrate+0xd23/0x1010 fs/ext4/migrate.c:588 __ext4_ioctl fs/ext4/ioctl.c:1694 [inline] ext4_ioctl+0x204b/0x48e0 fs/ext4/ioctl.c:1923 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->s_writepages_rwsem); lock(sb_internal); lock(&sbi->s_writepages_rwsem); rlock(sb_internal); *** DEADLOCK *** 3 locks held by syz.0.256/7158: #0: ffff88802fee4420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x60/0x200 fs/namespace.c:552 #1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: __ext4_ioctl fs/ext4/ioctl.c:1693 [inline] #1: ffff88807caa9700 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: ext4_ioctl+0x2043/0x48e0 fs/ext4/ioctl.c:1923 #2: ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_write fs/ext4/ext4.h:1808 [inline] #2: ffff88802fee2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_ext_migrate+0x2f3/0x1010 fs/ext4/migrate.c:438 stack backtrace: CPU: 0 UID: 0 PID: 7158 Comm: syz.0.256 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 percpu_down_read_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53 percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1916 [inline] sb_start_intwrite include/linux/fs.h:2099 [inline] ext4_evict_inode+0x2d6/0xee0 fs/ext4/inode.c:215 evict+0x504/0x9c0 fs/inode.c:810 ext4_ext_migrate+0xd23/0x1010 fs/ext4/migrate.c:588 __ext4_ioctl fs/ext4/ioctl.c:1694 [inline] ext4_ioctl+0x204b/0x48e0 fs/ext4/ioctl.c:1923 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f70e578f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f70e65e9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f70e59e5fa0 RCX: 00007f70e578f6c9 RDX: 0000000000000000 RSI: 0000000000006609 RDI: 0000000000000004 RBP: 00007f70e5811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f70e59e6038 R14: 00007f70e59e5fa0 R15: 00007ffe88ccf978 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup