====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc4-syzkaller-g19af4a4ed414 #0 Not tainted ------------------------------------------------------ syz-executor254/6025 is trying to acquire lock: ffff0000db54a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff0000db54a0e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0x160/0x328 fs/super.c:117 but task is already holding lock: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x7fc/0x2884 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_finish_claiming+0x218/0x3dc block/bdev.c:566 blkdev_get_by_dev+0x3f4/0x55c block/bdev.c:799 setup_bdev_super+0x68/0x51c fs/super.c:1484 mount_bdev+0x1a0/0x2b4 fs/super.c:1626 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 init_mount+0xe4/0x144 fs/init.c:25 do_mount_root+0x104/0x3e4 init/do_mounts.c:166 mount_root_generic+0x1f0/0x594 init/do_mounts.c:205 mount_block_root+0x6c/0x7c init/do_mounts.c:378 mount_root+0xb4/0xe4 init/do_mounts.c:405 prepare_namespace+0xdc/0x11c init/do_mounts.c:489 kernel_init_freeable+0x35c/0x474 init/main.c:1560 kernel_init+0x24/0x29c init/main.c:1437 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 -> #2 (bdev_lock ){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 bd_finish_claiming+0x84/0x3dc block/bdev.c:557 blkdev_get_by_dev+0x3f4/0x55c block/bdev.c:799 setup_bdev_super+0x68/0x51c fs/super.c:1484 mount_bdev+0x1a0/0x2b4 fs/super.c:1626 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 init_mount+0xe4/0x144 fs/init.c:25 do_mount_root+0x104/0x3e4 init/do_mounts.c:166 mount_root_generic+0x1f0/0x594 init/do_mounts.c:205 mount_block_root+0x6c/0x7c init/do_mounts.c:378 mount_root+0xb4/0xe4 init/do_mounts.c:405 prepare_namespace+0xdc/0x11c init/do_mounts.c:489 kernel_init_freeable+0x35c/0x474 init/main.c:1560 kernel_init+0x24/0x29c init/main.c:1437 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 blkdev_get_by_dev+0x114/0x55c block/bdev.c:786 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0xa60/0x1e44 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0xd50/0x2028 fs/reiserfs/super.c:2022 mount_bdev+0x1e8/0x2b4 fs/super.c:1629 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:638 vfs_get_tree+0x90/0x288 fs/super.c:1750 do_new_mount+0x25c/0x8c8 fs/namespace.c:3335 path_mount+0x590/0xe04 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3861 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 down_read+0x58/0x2fc kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x160/0x328 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0xa4/0x168 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x848/0x2884 block/ioctl.c:502 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> bdev_lock --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(bdev_lock); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor254/6025: #0: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff0000c1540c88 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x7fc/0x2884 block/ioctl.c:502 stack backtrace: CPU: 0 PID: 6025 Comm: syz-executor254 Not tainted 6.6.0-rc4-syzkaller-g19af4a4ed414 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x3370/0x75e8 kernel/locking/lockdep.c:5136 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5753 down_read+0x58/0x2fc kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0x160/0x328 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0xa4/0x168 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x848/0x2884 block/ioctl.c:502 blkdev_ioctl+0x35c/0xae4 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:857 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595