====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.5.450/5924 is trying to acquire lock: ffff8881408203f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:803 [inline] ffff8881408203f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_bmap+0x4f/0x3f0 fs/ext4/inode.c:3166 but task is already holding lock: ffff88807ed2c3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x317/0xcd0 fs/jbd2/journal.c:2499 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: __mutex_lock_common+0x1e5/0x2400 kernel/locking/mutex.c:596 mutex_lock_io_nested+0x43/0x60 kernel/locking/mutex.c:777 jbd2_journal_flush+0x285/0xcd0 fs/jbd2/journal.c:2489 ocfs2_journal_shutdown+0x41f/0xb00 fs/ocfs2/journal.c:1044 ocfs2_dismount_volume+0x1f9/0x890 fs/ocfs2/super.c:1892 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1438 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x426/0x4d0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:184 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #2 (&journal->j_barrier){+.+.}-{3:3}: __mutex_lock_common+0x1e5/0x2400 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 jbd2_journal_lock_updates+0x2ce/0x390 fs/jbd2/transaction.c:905 ext4_change_inode_journal_flag+0x18e/0x710 fs/ext4/inode.c:6135 ext4_ioctl_setflags fs/ext4/ioctl.c:448 [inline] ext4_fileattr_set+0xe61/0x1750 fs/ext4/ioctl.c:772 vfs_fileattr_set+0x859/0xb10 fs/ioctl.c:700 ioctl_setflags fs/ioctl.c:732 [inline] do_vfs_ioctl+0x1881/0x1f40 fs/ioctl.c:843 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: percpu_down_write+0x52/0x2f0 kernel/locking/percpu-rwsem.c:217 ext4_ind_migrate+0x247/0x8e0 fs/ext4/migrate.c:625 ext4_ioctl_setflags fs/ext4/ioctl.c:457 [inline] ext4_fileattr_set+0xf53/0x1750 fs/ext4/ioctl.c:772 vfs_fileattr_set+0x859/0xb10 fs/ioctl.c:700 ioctl_setflags fs/ioctl.c:732 [inline] do_vfs_ioctl+0x1881/0x1f40 fs/ioctl.c:843 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3120 [inline] check_prevs_add kernel/locking/lockdep.c:3239 [inline] validate_chain kernel/locking/lockdep.c:3855 [inline] __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120 lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 inode_lock_shared include/linux/fs.h:803 [inline] ext4_bmap+0x4f/0x3f0 fs/ext4/inode.c:3166 bmap+0xa2/0xd0 fs/inode.c:1820 jbd2_journal_bmap fs/jbd2/journal.c:981 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1795 [inline] jbd2_journal_flush+0x7e0/0xcd0 fs/jbd2/journal.c:2517 ext4_ioctl_checkpoint fs/ext4/ioctl.c:856 [inline] __ext4_ioctl fs/ext4/ioctl.c:1282 [inline] ext4_ioctl+0x31f7/0x3840 fs/ext4/ioctl.c:1291 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#9 --> &journal->j_barrier --> &journal->j_checkpoint_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_checkpoint_mutex); lock(&journal->j_barrier); lock(&journal->j_checkpoint_mutex); rlock(&sb->s_type->i_mutex_key#9); *** DEADLOCK *** 2 locks held by syz.5.450/5924: #0: ffff88807ed2c170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x2ce/0x390 fs/jbd2/transaction.c:905 #1: ffff88807ed2c3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x317/0xcd0 fs/jbd2/journal.c:2499 stack backtrace: CPU: 0 PID: 5924 Comm: syz.5.450 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3120 [inline] check_prevs_add kernel/locking/lockdep.c:3239 [inline] validate_chain kernel/locking/lockdep.c:3855 [inline] __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120 lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 inode_lock_shared include/linux/fs.h:803 [inline] ext4_bmap+0x4f/0x3f0 fs/ext4/inode.c:3166 bmap+0xa2/0xd0 fs/inode.c:1820 jbd2_journal_bmap fs/jbd2/journal.c:981 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1795 [inline] jbd2_journal_flush+0x7e0/0xcd0 fs/jbd2/journal.c:2517 ext4_ioctl_checkpoint fs/ext4/ioctl.c:856 [inline] __ext4_ioctl fs/ext4/ioctl.c:1282 [inline] ext4_ioctl+0x31f7/0x3840 fs/ext4/ioctl.c:1291 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f18ca1ee559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f18c8445028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f18ca474fa0 RCX: 00007f18ca1ee559 RDX: 00002000000003c0 RSI: 000000004004662b RDI: 0000000000000003 RBP: 00007f18ca285b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f18ca475038 R14: 00007f18ca474fa0 R15: 00007ffe752b7788