warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow ====================================================== WARNING: possible circular locking dependency detected 5.15.166-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.1156/9665 is trying to acquire lock: ffff8881408a03f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:799 [inline] ffff8881408a03f0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3163 but task is already holding lock: ffff8880299183f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x31c/0xc90 fs/jbd2/journal.c:2484 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+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596 mutex_lock_io_nested+0x45/0x60 kernel/locking/mutex.c:777 jbd2_journal_flush+0x290/0xc90 fs/jbd2/journal.c:2474 __ext4_ioctl fs/ext4/ioctl.c:1083 [inline] ext4_ioctl+0x24b0/0x5b80 fs/ext4/ioctl.c:1276 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #2 (&journal->j_barrier){+.+.}-{3:3}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1da/0x25a0 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+0x2aa/0x370 fs/jbd2/transaction.c:905 ext4_change_inode_journal_flag+0x1a8/0x6e0 fs/ext4/inode.c:6052 ext4_ioctl_setflags fs/ext4/ioctl.c:448 [inline] ext4_fileattr_set+0xdf4/0x1750 fs/ext4/ioctl.c:765 vfs_fileattr_set+0x8f3/0xd30 fs/ioctl.c:700 ioctl_setflags fs/ioctl.c:732 [inline] do_vfs_ioctl+0x1d85/0x2b70 fs/ioctl.c:843 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2688 do_writepages+0x481/0x730 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1d6/0x230 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] filemap_write_and_wait_range+0x19e/0x280 mm/filemap.c:704 __iomap_dio_rw+0x897/0x1f40 fs/iomap/direct-io.c:557 iomap_dio_rw+0x38/0x80 fs/iomap/direct-io.c:672 ext4_dio_write_iter fs/ext4/file.c:570 [inline] ext4_file_write_iter+0x1779/0x1990 fs/ext4/file.c:681 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacd/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 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:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498 inode_lock_shared include/linux/fs.h:799 [inline] ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3163 bmap+0xa1/0xd0 fs/inode.c:1791 jbd2_journal_bmap fs/jbd2/journal.c:981 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1796 [inline] jbd2_journal_flush+0x7a2/0xc90 fs/jbd2/journal.c:2502 ext4_ioctl_checkpoint fs/ext4/ioctl.c:849 [inline] __ext4_ioctl fs/ext4/ioctl.c:1267 [inline] ext4_ioctl+0x3249/0x5b80 fs/ext4/ioctl.c:1276 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 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); lock(&sb->s_type->i_mutex_key#9); *** DEADLOCK *** 2 locks held by syz.1.1156/9665: #0: ffff888029918170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x2aa/0x370 fs/jbd2/transaction.c:905 #1: ffff8880299183f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x31c/0xc90 fs/jbd2/journal.c:2484 stack backtrace: CPU: 1 PID: 9665 Comm: syz.1.1156 Not tainted 5.15.166-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498 inode_lock_shared include/linux/fs.h:799 [inline] ext4_bmap+0x4b/0x410 fs/ext4/inode.c:3163 bmap+0xa1/0xd0 fs/inode.c:1791 jbd2_journal_bmap fs/jbd2/journal.c:981 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1796 [inline] jbd2_journal_flush+0x7a2/0xc90 fs/jbd2/journal.c:2502 ext4_ioctl_checkpoint fs/ext4/ioctl.c:849 [inline] __ext4_ioctl fs/ext4/ioctl.c:1267 [inline] ext4_ioctl+0x3249/0x5b80 fs/ext4/ioctl.c:1276 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f079492eef9 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:00007f0792da8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f0794ae7f80 RCX: 00007f079492eef9 RDX: 0000000020000180 RSI: 000000004004662b RDI: 0000000000000006 RBP: 00007f07949a1046 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0794ae7f80 R15: 00007ffdbdd5bd18