====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/10523 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.5/10523: #0: (&fs_info->scrub_lock){+.+.}, at: [] btrfs_scrub_dev+0x506/0xcd0 fs/btrfs/scrub.c:4217 stack backtrace: CPU: 1 PID: 10523 Comm: syz-executor.5 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: 0033:0x7fb7211200f9 RSP: 002b:00007fb71f692168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb72123ff80 RCX: 00007fb7211200f9 RDX: 0000000020000100 RSI: 00000000c400941b RDI: 0000000000000004 RBP: 00007fb72117bae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff4d2cf09f R14: 00007fb71f692300 R15: 0000000000022000 XFS (loop4): Mounting V4 Filesystem XFS (loop4): Ending clean mount EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue XFS (loop2): Mounting V4 Filesystem XFS (loop2): Ending clean mount syz-executor.4 (10605) used greatest stack depth: 22880 bytes left XFS (loop4): Unmounting Filesystem XFS (loop0): Mounting V4 Filesystem XFS (loop0): Ending clean mount syz-executor.2 (10603) used greatest stack depth: 22720 bytes left XFS (loop2): Unmounting Filesystem XFS (loop0): Unmounting Filesystem XFS (loop3): Mounting V4 Filesystem BTRFS info (device loop5): enabling inode map caching BTRFS info (device loop5): trying to use backup root at mount time XFS (loop3): Ending clean mount BTRFS info (device loop5): use zlib compression BTRFS info (device loop5): enabling ssd optimizations BTRFS info (device loop5): using spread ssd allocation scheme BTRFS info (device loop5): using free space tree BTRFS info (device loop5): has skinny extents XFS (loop3): Unmounting Filesystem EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue XFS (loop4): Mounting V4 Filesystem XFS (loop4): Ending clean mount kauditd_printk_skb: 11 callbacks suppressed audit: type=1804 audit(1677372529.885:33): pid=10695 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir2445425970/syzkaller.ZJRGWa/31/file0/bus" dev="loop4" ino=41 res=1 audit: type=1804 audit(1677372529.995:34): pid=10695 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir2445425970/syzkaller.ZJRGWa/31/file0/bus" dev="loop4" ino=41 res=1 XFS (loop4): Unmounting Filesystem EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue XFS (loop2): Mounting V4 Filesystem XFS (loop2): Ending clean mount XFS (loop0): Mounting V4 Filesystem audit: type=1804 audit(1677372530.385:35): pid=10708 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir3255040792/syzkaller.XslEXX/22/file0/bus" dev="loop2" ino=41 res=1 EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue XFS (loop0): Ending clean mount EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue audit: type=1804 audit(1677372530.505:36): pid=10824 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.2" name="/root/syzkaller-testdir3255040792/syzkaller.XslEXX/22/file0/bus" dev="loop2" ino=41 res=1 XFS (loop2): Unmounting Filesystem XFS (loop0): Unmounting Filesystem XFS (loop3): Mounting V4 Filesystem audit: type=1804 audit(1677372530.595:37): pid=10719 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir1756983937/syzkaller.qZYkLP/39/file0/bus" dev="loop0" ino=41 res=1 audit: type=1804 audit(1677372530.685:38): pid=10836 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir1756983937/syzkaller.qZYkLP/39/file0/bus" dev="loop0" ino=41 res=1 XFS (loop3): Ending clean mount BTRFS info (device loop5): enabling inode map caching BTRFS info (device loop5): trying to use backup root at mount time BTRFS info (device loop5): use zlib compression ********************************************************** BTRFS info (device loop5): enabling ssd optimizations ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** BTRFS info (device loop5): using spread ssd allocation scheme ** ** BTRFS info (device loop5): using free space tree ** trace_printk() being used. Allocating extra memory. ** BTRFS info (device loop5): has skinny extents ** ** ** This means that this is a DEBUG kernel and it is ** ** unsafe for production use. ** audit: type=1804 audit(1677372531.285:39): pid=10755 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir2066191789/syzkaller.Oe9NQo/27/file0/bus" dev="loop3" ino=41 res=1 ** ** ** If you see this message and you are not debugging ** XFS (loop3): Unmounting Filesystem EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue audit: type=1804 audit(1677372531.325:40): pid=10755 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir2066191789/syzkaller.Oe9NQo/27/file0/bus" dev="loop3" ino=41 res=1 ** the kernel, report this immediately to your vendor! ** ** ** ** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE ** ********************************************************** EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue BTRFS info (device loop5): enabling inode map caching BTRFS info (device loop5): trying to use backup root at mount time BTRFS info (device loop5): use zlib compression BTRFS info (device loop5): enabling ssd optimizations BTRFS info (device loop5): using spread ssd allocation scheme BTRFS info (device loop5): using free space tree BTRFS info (device loop5): has skinny extents ntfs: (device loop4): parse_options(): Option utf8 is no longer supported, using option nls=utf8. Please use option nls=utf8 in the future and make sure utf8 is compiled either as a module or into the kernel. ntfs: (device loop4): read_ntfs_boot_sector(): Hot-fix: Recovering invalid primary boot sector from backup copy. ntfs: volume version 3.1. NILFS (loop0): invalid segment: Checksum error in segment payload NILFS (loop0): trying rollback from an earlier position NILFS (loop0): recovery complete NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds ntfs: (device loop4): parse_options(): Option utf8 is no longer supported, using option nls=utf8. Please use option nls=utf8 in the future and make sure utf8 is compiled either as a module or into the kernel. ntfs: (device loop4): read_ntfs_boot_sector(): Hot-fix: Recovering invalid primary boot sector from backup copy.