From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f207.google.com (mail-il1-f207.google.com [209.85.166.207]) (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 CA0A04C83 for ; Thu, 5 Dec 2024 04:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733371409; cv=none; b=PvEqDYi518qJ6BxJO4ZHYxUBvvBedoKLu7ZOsjKPHEwxoYvdM3+W0xJz+KpQY8bDJuQ3TA16OwqZOs3cqagolPJvqcJpX0zk0zZXzMEnhzXBXgK4oTRyHGn0Dgi3rZpXcywti08DQOlIGGmpHplBTegk2sklk6l3pJTq7oNcvOk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733371409; c=relaxed/simple; bh=B0UPE7YGd7Ngfk7Yvttlp5aIzUFGcYLfdxETEY4G5qU=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=lqR7hitWogurkVVs+/GuKxnihdYNfbK8oQeJ8iuA5fnWHUhzqOnFtOAfx5lFBSvgz4BFO5VylDDeA/bN/mncPxnMei4/7gKbc1Voo9QTeWFYPaDjGLThxoEq+N1FK3k7phqb7iWJVpXQOAS58W4hqVcstTRb2m27CzNEa0BMgZ4= 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=209.85.166.207 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-il1-f207.google.com with SMTP id e9e14a558f8ab-3a76690f813so5035535ab.2 for ; Wed, 04 Dec 2024 20:03:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733371406; x=1733976206; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=OmPMIvGUcaEEXWOl+xY0Ue7t7j0C3yIAMWikuEG04iQ=; b=SQzfeSc4P/Opoq8Rtco227OKjyWzpyF1K6jiUAYD2ZywrBI2QNBc+zupzFz2YN0DqI hgrRcHLAa6H9bnjf1J0vaNv4prWsYchuGzQWDRFulZbqaivbfFgHf6p/tw+ynfEI1bpC paH+ShUgFihCd/mMSpz5ul3SIkOVAvSr+KK22DdvKVwh0JMXnn6oy215Wl21/zWS+Cv8 lmekclCDNUD+ljP6YkBx6pp8BrWwaclkoVU7hWKY+UpPILlTJrF6y/felpBguNzJKOxF zVNxCrWPZcY2TrL/tRgAXXQxkdtTG7Gj1fwaSGc0/Tz0Lcg29f8tEq7l8Ev8nOnXw9fM aC6A== X-Forwarded-Encrypted: i=1; AJvYcCU/FqoZlg+Vbu3WMIQW6oJv3h2X7LXXf9Emac35ODDNTJF34YTw5Ay8eO4fQCWJnnqAmqqLU+gAONOkr7o=@vger.kernel.org X-Gm-Message-State: AOJu0YyCahvyMQJedXHcCqxfk/D6pmjPZDSlWUpZ8t7mWuZ1n4jVlc5y qwrOxt0RTLKvWXk1QvXEchy9WzQ8NN8IwlMb1U+d5lJiu9xF0g+X1W1s/x8noAqyWgt/1n84vAO wk1ulIONOOUgkHmVVBSMV+drBiQNwGoI/ppB/ynmPzPpxBDoVG5puqPk= X-Google-Smtp-Source: AGHT+IEHaBQ9uVYQVaRC9NA1c6zszP4aXA22I2iVLzc0Ijn+UzAEB3i1kiiODas+CHvIuip6LvsP5CmdDuldtIkcH3lLl9xqBsFh Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a92:c24f:0:b0:3a7:c5ff:e5e2 with SMTP id e9e14a558f8ab-3a7f99b1233mr119494585ab.0.1733371405925; Wed, 04 Dec 2024 20:03:25 -0800 (PST) Date: Wed, 04 Dec 2024 20:03:25 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6751260d.050a0220.17bd51.0085.GAE@google.com> Subject: [syzbot] [btrfs?] possible deadlock in __btrfs_commit_inode_delayed_items From: syzbot To: clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: f486c8aa16b8 Add linux-next specific files for 20241128 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=111705e8580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e348a4873516af92 dashboard link: https://syzkaller.appspot.com/bug?extid=71d80f05e434f9bfaaec 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/beb58ebb63cf/disk-f486c8aa.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b241b5609e64/vmlinux-f486c8aa.xz kernel image: https://storage.googleapis.com/syzbot-assets/c9d817f665f2/bzImage-f486c8aa.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+71d80f05e434f9bfaaec@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.12.0-next-20241128-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u8:12/6861 is trying to acquire lock: ffff88803171b3b8 (btrfs-tree-01){++++}-{4:4}, at: btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146 but task is already holding lock: ffff888071adc860 (&delayed_node->mutex){+.+.}-{4:4}, at: btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:830 [inline] ffff888071adc860 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_commit_inode_delayed_items+0x1c4/0x24a0 fs/btrfs/delayed-inode.c:1126 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&delayed_node->mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 __btrfs_release_delayed_node+0xa5/0xaf0 fs/btrfs/delayed-inode.c:268 btrfs_evict_inode+0x752/0x1080 fs/btrfs/inode.c:5374 evict+0x4e8/0x9a0 fs/inode.c:796 dispose_list fs/inode.c:845 [inline] prune_icache_sb+0x239/0x2f0 fs/inode.c:1033 super_cache_scan+0x38c/0x4b0 fs/super.c:223 do_shrink_slab+0x72d/0x1160 mm/shrinker.c:437 shrink_slab_memcg mm/shrinker.c:550 [inline] shrink_slab+0x878/0x14d0 mm/shrinker.c:628 shrink_one+0x43b/0x850 mm/vmscan.c:4836 shrink_many mm/vmscan.c:4897 [inline] lru_gen_shrink_node mm/vmscan.c:4975 [inline] shrink_node+0x37c5/0x3e50 mm/vmscan.c:5956 kswapd_shrink_node mm/vmscan.c:6785 [inline] balance_pgdat mm/vmscan.c:6977 [inline] kswapd+0x1ca9/0x36f0 mm/vmscan.c:7246 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #3 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __fs_reclaim_acquire mm/page_alloc.c:3887 [inline] fs_reclaim_acquire+0x88/0x130 mm/page_alloc.c:3901 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4055 [inline] slab_alloc_node mm/slub.c:4133 [inline] __kmalloc_cache_noprof+0x41/0x390 mm/slub.c:4309 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] kobject_uevent_env+0x28b/0x8e0 lib/kobject_uevent.c:540 loop_set_size drivers/block/loop.c:233 [inline] loop_set_status+0x5f0/0x8f0 drivers/block/loop.c:1285 lo_ioctl+0xcbc/0x1f50 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 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 -> #2 (&q->q_usage_counter(io)#17){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3091 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 btrfs_submit_chunk fs/btrfs/bio.c:745 [inline] btrfs_submit_bbio+0xf93/0x18e0 fs/btrfs/bio.c:773 read_extent_buffer_pages+0x65a/0x910 fs/btrfs/extent_io.c:3558 btrfs_read_extent_buffer+0xd9/0x770 fs/btrfs/disk-io.c:229 read_block_for_search+0x79e/0xbb0 fs/btrfs/ctree.c:1619 btrfs_search_slot+0x121b/0x3150 fs/btrfs/ctree.c:2236 btrfs_init_root_free_objectid+0x148/0x330 fs/btrfs/disk-io.c:4837 btrfs_init_fs_root fs/btrfs/disk-io.c:1137 [inline] btrfs_get_root_ref+0x5d7/0xc30 fs/btrfs/disk-io.c:1364 btrfs_get_fs_root fs/btrfs/disk-io.c:1416 [inline] open_ctree+0x2470/0x2a30 fs/btrfs/disk-io.c:3532 btrfs_fill_super fs/btrfs/super.c:972 [inline] btrfs_get_tree_super fs/btrfs/super.c:1894 [inline] btrfs_get_tree+0x1274/0x1a10 fs/btrfs/super.c:2105 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 fc_mount+0x1b/0xb0 fs/namespace.c:1231 btrfs_get_tree_subvol fs/btrfs/super.c:2068 [inline] btrfs_get_tree+0x65b/0x1a10 fs/btrfs/super.c:2106 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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 -> #1 (btrfs-tree-00){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1649 btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146 btrfs_tree_read_lock fs/btrfs/locking.h:178 [inline] read_block_for_search+0x718/0xbb0 fs/btrfs/ctree.c:1613 btrfs_search_slot+0x121b/0x3150 fs/btrfs/ctree.c:2236 btrfs_init_root_free_objectid+0x148/0x330 fs/btrfs/disk-io.c:4837 btrfs_init_fs_root fs/btrfs/disk-io.c:1137 [inline] btrfs_get_root_ref+0x5d7/0xc30 fs/btrfs/disk-io.c:1364 btrfs_get_fs_root fs/btrfs/disk-io.c:1416 [inline] open_ctree+0x2470/0x2a30 fs/btrfs/disk-io.c:3532 btrfs_fill_super fs/btrfs/super.c:972 [inline] btrfs_get_tree_super fs/btrfs/super.c:1894 [inline] btrfs_get_tree+0x1274/0x1a10 fs/btrfs/super.c:2105 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 fc_mount+0x1b/0xb0 fs/namespace.c:1231 btrfs_get_tree_subvol fs/btrfs/super.c:2068 [inline] btrfs_get_tree+0x65b/0x1a10 fs/btrfs/super.c:2106 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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 -> #0 (btrfs-tree-01){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1649 btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146 btrfs_tree_read_lock fs/btrfs/locking.h:178 [inline] btrfs_read_lock_root_node+0x3f/0xd0 fs/btrfs/locking.c:267 btrfs_search_slot_get_root fs/btrfs/ctree.c:1790 [inline] btrfs_search_slot+0x4f7/0x3150 fs/btrfs/ctree.c:2112 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4350 btrfs_insert_delayed_item fs/btrfs/delayed-inode.c:758 [inline] btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:836 [inline] __btrfs_commit_inode_delayed_items+0xd5d/0x24a0 fs/btrfs/delayed-inode.c:1126 __btrfs_run_delayed_items+0x213/0x490 fs/btrfs/delayed-inode.c:1171 flush_space+0x24a/0xcf0 fs/btrfs/space-info.c:775 btrfs_async_reclaim_metadata_space+0x113/0x350 fs/btrfs/space-info.c:1105 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: btrfs-tree-01 --> fs_reclaim --> &delayed_node->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&delayed_node->mutex); lock(fs_reclaim); lock(&delayed_node->mutex); rlock(btrfs-tree-01); *** DEADLOCK *** 5 locks held by kworker/u8:12/6861: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000369fd00 ((work_completion)(&fs_info->async_reclaim_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000369fd00 ((work_completion)(&fs_info->async_reclaim_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffff888034ba2470 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x405/0xda0 fs/btrfs/transaction.c:288 #3: ffff888034ba2498 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x405/0xda0 fs/btrfs/transaction.c:288 #4: ffff888071adc860 (&delayed_node->mutex){+.+.}-{4:4}, at: btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:830 [inline] #4: ffff888071adc860 (&delayed_node->mutex){+.+.}-{4:4}, at: __btrfs_commit_inode_delayed_items+0x1c4/0x24a0 fs/btrfs/delayed-inode.c:1126 stack backtrace: CPU: 0 UID: 0 PID: 6861 Comm: kworker/u8:12 Not tainted 6.12.0-next-20241128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound btrfs_async_reclaim_metadata_space Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read_nested+0xb5/0xa50 kernel/locking/rwsem.c:1649 btrfs_tree_read_lock_nested+0x2f/0x250 fs/btrfs/locking.c:146 btrfs_tree_read_lock fs/btrfs/locking.h:178 [inline] btrfs_read_lock_root_node+0x3f/0xd0 fs/btrfs/locking.c:267 btrfs_search_slot_get_root fs/btrfs/ctree.c:1790 [inline] btrfs_search_slot+0x4f7/0x3150 fs/btrfs/ctree.c:2112 btrfs_insert_empty_items+0x9c/0x1a0 fs/btrfs/ctree.c:4350 btrfs_insert_delayed_item fs/btrfs/delayed-inode.c:758 [inline] btrfs_insert_delayed_items fs/btrfs/delayed-inode.c:836 [inline] __btrfs_commit_inode_delayed_items+0xd5d/0x24a0 fs/btrfs/delayed-inode.c:1126 __btrfs_run_delayed_items+0x213/0x490 fs/btrfs/delayed-inode.c:1171 flush_space+0x24a/0xcf0 fs/btrfs/space-info.c:775 btrfs_async_reclaim_metadata_space+0x113/0x350 fs/btrfs/space-info.c:1105 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 --- 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