====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.4.56/4743 is trying to acquire lock: ffff8000210390f0 (&journal->j_mutex){+.+.}-{3:3}, at: reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline] ffff8000210390f0 (&journal->j_mutex){+.+.}-{3:3}, at: lock_journal fs/reiserfs/journal.c:534 [inline] ffff8000210390f0 (&journal->j_mutex){+.+.}-{3:3}, at: do_journal_begin_r+0x2c4/0xde8 fs/reiserfs/journal.c:3049 but task is already holding lock: ffff0000df5e0460 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1e8 fs/namespace.c:446 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_writers#21){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1891 [inline] sb_start_write+0x74/0x2ac include/linux/fs.h:1966 mnt_want_write_file+0x64/0x1e8 fs/namespace.c:446 reiserfs_ioctl+0x114/0x450 fs/reiserfs/ioctl.c:103 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #1 (&sbi->lock){+.+.}-{3:3}: __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 reiserfs_write_lock_nested+0x68/0xd8 fs/reiserfs/lock.c:78 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:815 [inline] lock_journal fs/reiserfs/journal.c:534 [inline] do_journal_begin_r+0x2d0/0xde8 fs/reiserfs/journal.c:3049 journal_begin+0x110/0x2f4 fs/reiserfs/journal.c:3257 reiserfs_fill_super+0x11ec/0x1d40 fs/reiserfs/super.c:2104 mount_bdev+0x264/0x358 fs/super.c:1443 get_super_block+0x44/0x58 fs/reiserfs/super.c:2601 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632 vfs_get_tree+0x90/0x274 fs/super.c:1573 do_new_mount+0x228/0x810 fs/namespace.c:3078 path_mount+0x5b4/0xe78 fs/namespace.c:3408 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount fs/namespace.c:3606 [inline] __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3606 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #0 (&journal->j_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline] lock_journal fs/reiserfs/journal.c:534 [inline] do_journal_begin_r+0x2c4/0xde8 fs/reiserfs/journal.c:3049 journal_begin+0x110/0x2f4 fs/reiserfs/journal.c:3257 reiserfs_dirty_inode+0x100/0x200 fs/reiserfs/super.c:710 __mark_inode_dirty+0x2e8/0x11cc fs/fs-writeback.c:2443 mark_inode_dirty include/linux/fs.h:2546 [inline] reiserfs_ioctl+0x364/0x450 fs/reiserfs/ioctl.c:111 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 other info that might help us debug this: Chain exists of: &journal->j_mutex --> &sbi->lock --> sb_writers#21 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_writers#21); lock(&sbi->lock); lock(sb_writers#21); lock(&journal->j_mutex); *** DEADLOCK *** 1 lock held by syz.4.56/4743: #0: ffff0000df5e0460 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write_file+0x64/0x1e8 fs/namespace.c:446 stack backtrace: CPU: 1 PID: 4743 Comm: syz.4.56 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x240/0x2d4 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x293c/0x6544 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x644 kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f38 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 reiserfs_mutex_lock_safe fs/reiserfs/reiserfs.h:814 [inline] lock_journal fs/reiserfs/journal.c:534 [inline] do_journal_begin_r+0x2c4/0xde8 fs/reiserfs/journal.c:3049 journal_begin+0x110/0x2f4 fs/reiserfs/journal.c:3257 reiserfs_dirty_inode+0x100/0x200 fs/reiserfs/super.c:710 __mark_inode_dirty+0x2e8/0x11cc fs/fs-writeback.c:2443 mark_inode_dirty include/linux/fs.h:2546 [inline] reiserfs_ioctl+0x364/0x450 fs/reiserfs/ioctl.c:111 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585