warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow ====================================================== WARNING: possible circular locking dependency detected 6.1.97-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.270/5064 is trying to acquire lock: ffff888140ca8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline] ffff888140ca8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3176 but task is already holding lock: ffff88807efce3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x323/0xc40 fs/jbd2/journal.c:2478 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] mutex_lock_io_nested+0x134/0xab0 kernel/locking/mutex.c:833 jbd2_journal_flush+0x29b/0xc40 fs/jbd2/journal.c:2468 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1086 [inline] __ext4_ioctl fs/ext4/ioctl.c:1594 [inline] ext4_ioctl+0x3986/0x5f60 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&journal->j_barrier){+.+.}-{3:3}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747 jbd2_journal_lock_updates+0x2b0/0x380 fs/jbd2/transaction.c:904 ext4_change_inode_journal_flag+0x1a8/0x6e0 fs/ext4/inode.c:6120 ext4_ioctl_setflags fs/ext4/ioctl.c:688 [inline] ext4_fileattr_set+0xe04/0x1770 fs/ext4/ioctl.c:1008 vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:696 ioctl_setflags fs/ioctl.c:728 [inline] do_vfs_ioctl+0x1cd1/0x2a90 fs/ioctl.c:839 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl+0x81/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 percpu_down_write+0x50/0x2f0 kernel/locking/percpu-rwsem.c:227 ext4_ind_migrate+0x254/0x760 fs/ext4/migrate.c:624 ext4_ioctl_setflags fs/ext4/ioctl.c:697 [inline] ext4_fileattr_set+0xe9b/0x1770 fs/ext4/ioctl.c:1008 vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:696 ioctl_setflags fs/ioctl.c:728 [inline] do_vfs_ioctl+0x1cd1/0x2a90 fs/ioctl.c:839 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl+0x81/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&sb->s_type->i_mutex_key#8){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 down_read+0xad/0xa30 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:768 [inline] ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3176 bmap+0xa1/0xd0 fs/inode.c:1842 jbd2_journal_bmap fs/jbd2/journal.c:977 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1794 [inline] jbd2_journal_flush+0x5b5/0xc40 fs/jbd2/journal.c:2496 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1086 [inline] __ext4_ioctl fs/ext4/ioctl.c:1594 [inline] ext4_ioctl+0x3986/0x5f60 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#8 --> &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); lock(&sb->s_type->i_mutex_key#8); *** DEADLOCK *** 2 locks held by syz.1.270/5064: #0: ffff88807efce170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x2b0/0x380 fs/jbd2/transaction.c:904 #1: ffff88807efce3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x323/0xc40 fs/jbd2/journal.c:2478 stack backtrace: CPU: 1 PID: 5064 Comm: syz.1.270 Not tainted 6.1.97-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 check_noncircular+0x2fa/0x3b0 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+0x1661/0x5950 kernel/locking/lockdep.c:3825 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 down_read+0xad/0xa30 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:768 [inline] ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3176 bmap+0xa1/0xd0 fs/inode.c:1842 jbd2_journal_bmap fs/jbd2/journal.c:977 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1794 [inline] jbd2_journal_flush+0x5b5/0xc40 fs/jbd2/journal.c:2496 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1086 [inline] __ext4_ioctl fs/ext4/ioctl.c:1594 [inline] ext4_ioctl+0x3986/0x5f60 fs/ext4/ioctl.c:1614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc2cf975bd9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc2d0661048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc2cfb041e8 RCX: 00007fc2cf975bd9 RDX: 0000000020000180 RSI: 000000004004662b RDI: 000000000000000c RBP: 00007fc2cf9e4e60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fc2cfb041e8 R15: 00007fff03e8c2c8