warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow ====================================================== WARNING: possible circular locking dependency detected 6.2.0-syzkaller-13534-gb01fe98d34f3 #0 Not tainted ------------------------------------------------------ syz-executor.0/22604 is trying to acquire lock: ffff88814b870400 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline] ffff88814b870400 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: ext4_bmap+0x4f/0x410 fs/ext4/inode.c:3242 but task is already holding lock: ffff88802a8783f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x327/0xc40 fs/jbd2/journal.c:2473 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+0x23e/0x630 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 mutex_lock_io_nested+0x47/0x60 kernel/locking/mutex.c:833 jbd2_journal_flush+0x29f/0xc40 fs/jbd2/journal.c:2463 ext4_ioctl_group_add+0x1f5/0x530 fs/ext4/ioctl.c:947 __ext4_ioctl fs/ext4/ioctl.c:1370 [inline] ext4_ioctl+0x1d94/0x6260 fs/ext4/ioctl.c:1607 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:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&journal->j_barrier){+.+.}-{3:3}: lock_acquire+0x23e/0x630 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799 jbd2_journal_lock_updates+0x2b4/0x380 fs/jbd2/transaction.c:904 ext4_change_inode_journal_flag+0x1a6/0x6c0 fs/ext4/inode.c:6156 ext4_ioctl_setflags fs/ext4/ioctl.c:684 [inline] ext4_fileattr_set+0xe17/0x1790 fs/ext4/ioctl.c:1001 vfs_fileattr_set+0x8f7/0xd40 fs/ioctl.c:696 ioctl_setflags fs/ioctl.c:728 [inline] do_vfs_ioctl+0x1e47/0x2b10 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:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: lock_acquire+0x23e/0x630 kernel/locking/lockdep.c:5669 percpu_down_write+0x54/0x2f0 kernel/locking/percpu-rwsem.c:227 ext4_ind_migrate+0x258/0x760 fs/ext4/migrate.c:624 ext4_ioctl_setflags fs/ext4/ioctl.c:693 [inline] ext4_fileattr_set+0xeae/0x1790 fs/ext4/ioctl.c:1001 vfs_fileattr_set+0x8f7/0xd40 fs/ioctl.c:696 ioctl_setflags fs/ioctl.c:728 [inline] do_vfs_ioctl+0x1e47/0x2b10 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:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&sb->s_type->i_mutex_key#7){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x23e/0x630 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:768 [inline] ext4_bmap+0x4f/0x410 fs/ext4/inode.c:3242 bmap+0xa5/0xe0 fs/inode.c:1799 jbd2_journal_bmap fs/jbd2/journal.c:976 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1788 [inline] jbd2_journal_flush+0x5b9/0xc40 fs/jbd2/journal.c:2491 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1079 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x3abc/0x6260 fs/ext4/ioctl.c:1607 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:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#7 --> &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#7); *** DEADLOCK *** 2 locks held by syz-executor.0/22604: #0: ffff88802a878170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x2b4/0x380 fs/jbd2/transaction.c:904 #1: ffff88802a8783f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x327/0xc40 fs/jbd2/journal.c:2473 stack backtrace: CPU: 0 PID: 22604 Comm: syz-executor.0 Not tainted 6.2.0-syzkaller-13534-gb01fe98d34f3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056 lock_acquire+0x23e/0x630 kernel/locking/lockdep.c:5669 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:768 [inline] ext4_bmap+0x4f/0x410 fs/ext4/inode.c:3242 bmap+0xa5/0xe0 fs/inode.c:1799 jbd2_journal_bmap fs/jbd2/journal.c:976 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1788 [inline] jbd2_journal_flush+0x5b9/0xc40 fs/jbd2/journal.c:2491 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1079 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x3abc/0x6260 fs/ext4/ioctl.c:1607 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:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f530f88c0f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f53105d2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f530f9abf80 RCX: 00007f530f88c0f9 RDX: 0000000020000040 RSI: 000000004004662b RDI: 0000000000000003 RBP: 00007f530f8e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0afd76cf R14: 00007f53105d2300 R15: 0000000000022000