====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/10487 is trying to acquire lock: ("%s-%s""btrfs", name){+.+.}, at: [] flush_workqueue+0xcb/0x1310 kernel/workqueue.c:2622 but task is already holding lock: (&fs_info->scrub_lock){+.+.}, at: [] btrfs_scrub_dev+0x506/0xcd0 fs/btrfs/scrub.c:4217 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&fs_info->scrub_lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 btrfs_scrub_dev+0x1f3/0xcd0 fs/btrfs/scrub.c:4150 btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline] btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 -> #2 (&fs_devs->device_list_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 __reada_start_machine fs/btrfs/reada.c:765 [inline] reada_start_machine_worker+0x1d2/0xa90 fs/btrfs/reada.c:746 normal_work_helper+0x304/0x1330 fs/btrfs/async-thread.c:376 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406 -> #1 ((&work->normal_work)){+.+.}: process_one_work+0x736/0x14a0 kernel/workqueue.c:2093 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406 -> #0 ("%s-%s""btrfs", name){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2625 drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2790 destroy_workqueue+0x71/0x710 kernel/workqueue.c:4116 __btrfs_destroy_workqueue fs/btrfs/async-thread.c:436 [inline] btrfs_destroy_workqueue+0xf8/0x630 fs/btrfs/async-thread.c:447 scrub_workers_put+0x90/0x1a0 fs/btrfs/scrub.c:4075 btrfs_scrub_dev+0x536/0xcd0 fs/btrfs/scrub.c:4219 btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline] btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 other info that might help us debug this: Chain exists of: "%s-%s""btrfs", name --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->scrub_lock); lock(&fs_devs->device_list_mutex); lock(&fs_info->scrub_lock); lock("%s-%s""btrfs", name); *** DEADLOCK *** 1 lock held by syz-executor.4/10487: #0: (&fs_info->scrub_lock){+.+.}, at: [] btrfs_scrub_dev+0x506/0xcd0 fs/btrfs/scrub.c:4217 stack backtrace: CPU: 1 PID: 10487 Comm: syz-executor.4 Not tainted 4.14.307-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_workqueue+0xfa/0x1310 kernel/workqueue.c:2625 drain_workqueue+0x177/0x3e0 kernel/workqueue.c:2790 destroy_workqueue+0x71/0x710 kernel/workqueue.c:4116 __btrfs_destroy_workqueue fs/btrfs/async-thread.c:436 [inline] btrfs_destroy_workqueue+0xf8/0x630 fs/btrfs/async-thread.c:447 scrub_workers_put+0x90/0x1a0 fs/btrfs/scrub.c:4075 btrfs_scrub_dev+0x536/0xcd0 fs/btrfs/scrub.c:4219 btrfs_ioctl_scrub fs/btrfs/ioctl.c:4451 [inline] btrfs_ioctl+0xba8/0x5b20 fs/btrfs/ioctl.c:5681 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7f7cd90620f9 RSP: 002b:00007f7cd75d4168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f7cd9181f80 RCX: 00007f7cd90620f9 RDX: 0000000020000100 RSI: 00000000c400941b RDI: 0000000000000004 RBP: 00007f7cd90bdae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe324ec98f R14: 00007f7cd75d4300 R15: 0000000000022000 BTRFS info (device loop0): enabling inode map caching BTRFS info (device loop0): trying to use backup root at mount time BTRFS info (device loop0): use zlib compression BTRFS info (device loop0): enabling ssd optimizations BTRFS info (device loop0): using spread ssd allocation scheme BTRFS info (device loop0): using free space tree BTRFS info (device loop0): has skinny extents audit: type=1800 audit(1677644670.952:2): pid=10555 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop0" ino=263 res=0 audit: type=1800 audit(1677644671.032:3): pid=10587 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="bus" dev="loop0" ino=263 res=0 BTRFS info (device loop3): enabling inode map caching BTRFS info (device loop3): trying to use backup root at mount time BTRFS info (device loop3): use zlib compression BTRFS info (device loop3): enabling ssd optimizations BTRFS info (device loop3): using spread ssd allocation scheme BTRFS info (device loop3): using free space tree BTRFS info (device loop3): has skinny extents BTRFS info (device loop3): enabling inode map caching BTRFS info (device loop3): trying to use backup root at mount time BTRFS info (device loop3): use zlib compression BTRFS info (device loop3): enabling ssd optimizations BTRFS info (device loop3): using spread ssd allocation scheme BTRFS info (device loop3): using free space tree BTRFS info (device loop3): has skinny extents BTRFS info (device loop1): enabling inode map caching BTRFS info (device loop1): trying to use backup root at mount time BTRFS info (device loop1): use zlib compression BTRFS info (device loop1): enabling ssd optimizations BTRFS info (device loop1): using spread ssd allocation scheme BTRFS info (device loop1): using free space tree BTRFS info (device loop1): has skinny extents audit: type=1800 audit(1677644672.642:4): pid=10816 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="bus" dev="loop1" ino=263 res=0 audit: type=1800 audit(1677644672.722:5): pid=10832 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.5" name="bus" dev="loop1" ino=263 res=0 audit: type=1800 audit(1677644672.762:6): pid=10844 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop1" ino=263 res=0 9pnet: Insufficient options for proto=fd L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details. capability: warning: `syz-executor.1' uses deprecated v2 capabilities in a way that may be insecure 9pnet: Insufficient options for proto=fd Zero length message leads to an empty skb EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue NILFS (loop0): unrecognized mount option "" BTRFS info (device loop4): enabling inode map caching BTRFS info (device loop4): trying to use backup root at mount time BTRFS info (device loop4): use zlib compression BTRFS: device fsid a6a605fc-d5f1-4e66-8595-3726e2b761d6 devid 1 transid 8 /dev/loop2 BTRFS info (device loop4): enabling ssd optimizations BTRFS info (device loop4): using spread ssd allocation scheme BTRFS error (device loop2): unsupported checksum algorithm 3 BTRFS info (device loop4): using free space tree BTRFS info (device loop4): has skinny extents BTRFS error (device loop2): superblock checksum mismatch BTRFS error (device loop2): open_ctree failed audit: type=1800 audit(1677644675.735:7): pid=11158 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="bus" dev="loop4" ino=263 res=0 NILFS (loop0): unrecognized mount option "" unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue XFS (loop2): Superblock has unknown read-only compatible features (0x8) enabled. XFS (loop2): Attempted to mount read-only compatible filesystem read-write. XFS (loop2): Filesystem can only be safely mounted read only. XFS (loop2): SB validate failed with error -22. audit: type=1804 audit(1677644677.775:8): pid=11439 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir4217787045/syzkaller.RO2g2F/84/bus" dev="sda1" ino=14120 res=1 EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue audit: type=1800 audit(1677644677.775:9): pid=11439 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.4" name="bus" dev="sda1" ino=14120 res=0 BTRFS info (device loop1): enabling inode map caching BTRFS info (device loop1): trying to use backup root at mount time BTRFS info (device loop1): use zlib compression BTRFS info (device loop1): enabling ssd optimizations BTRFS info (device loop1): using spread ssd allocation scheme BTRFS info (device loop1): using free space tree BTRFS info (device loop1): has skinny extents audit: type=1800 audit(1677644678.215:10): pid=11426 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="bus" dev="loop1" ino=263 res=0 audit: type=1804 audit(1677644679.265:11): pid=11518 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir2008868507/syzkaller.aqWH1K/87/bus" dev="sda1" ino=14129 res=1 audit: type=1800 audit(1677644679.265:12): pid=11518 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.2" name="bus" dev="sda1" ino=14129 res=0