====================================================== WARNING: possible circular locking dependency detected 5.15.161-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/4737 is trying to acquire lock: ffff88807f5403f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:71 but task is already holding lock: ffff8880570cb5c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] ffff8880570cb5c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4269 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#9){++++}-{3:3}: 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:3152 bmap+0xa1/0xd0 fs/inode.c:1756 jbd2_journal_bmap fs/jbd2/journal.c:980 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1790 [inline] jbd2_journal_flush+0x7a2/0xc90 fs/jbd2/journal.c:2496 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 -> #0 (&journal->j_checkpoint_mutex){+.+.}-{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 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596 mutex_lock_io_nested+0x45/0x60 kernel/locking/mutex.c:777 __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:71 add_transaction_credits+0x950/0xc00 fs/jbd2/transaction.c:299 start_this_handle+0x747/0x1570 fs/jbd2/transaction.c:423 jbd2__journal_start+0x2d1/0x5c0 fs/jbd2/transaction.c:521 __ext4_journal_start_sb+0x175/0x370 fs/ext4/ext4_jbd2.c:105 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] __ext4_unlink+0x3a7/0xae0 fs/ext4/namei.c:3265 ext4_unlink+0x1a9/0x530 fs/ext4/namei.c:3324 vfs_unlink+0x359/0x5f0 fs/namei.c:4280 do_unlinkat+0x4a3/0x950 fs/namei.c:4348 __do_sys_unlink fs/namei.c:4396 [inline] __se_sys_unlink fs/namei.c:4394 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4394 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: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#9); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#9); lock(&journal->j_checkpoint_mutex); *** DEADLOCK *** 3 locks held by syz-executor.0/4737: #0: ffff88807f4c4460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377 #1: ffff88805dde67a0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline] #1: ffff88805dde67a0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_unlinkat+0x266/0x950 fs/namei.c:4331 #2: ffff8880570cb5c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #2: ffff8880570cb5c8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4269 stack backtrace: CPU: 0 PID: 4737 Comm: syz-executor.0 Not tainted 5.15.161-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+0x1e3/0x2d0 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 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596 mutex_lock_io_nested+0x45/0x60 kernel/locking/mutex.c:777 __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:71 add_transaction_credits+0x950/0xc00 fs/jbd2/transaction.c:299 start_this_handle+0x747/0x1570 fs/jbd2/transaction.c:423 jbd2__journal_start+0x2d1/0x5c0 fs/jbd2/transaction.c:521 __ext4_journal_start_sb+0x175/0x370 fs/ext4/ext4_jbd2.c:105 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] __ext4_unlink+0x3a7/0xae0 fs/ext4/namei.c:3265 ext4_unlink+0x1a9/0x530 fs/ext4/namei.c:3324 vfs_unlink+0x359/0x5f0 fs/namei.c:4280 do_unlinkat+0x4a3/0x950 fs/namei.c:4348 __do_sys_unlink fs/namei.c:4396 [inline] __se_sys_unlink fs/namei.c:4394 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4394 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: 0033:0x7f6625a4e6d7 Code: 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffdc3a86588 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6625a4e6d7 RDX: 00007ffdc3a865b0 RSI: 00007ffdc3a86640 RDI: 00007ffdc3a86640 RBP: 00007ffdc3a86640 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffdc3a876f0 R13: 00007f6625aab6c6 R14: 0000000000029bfc R15: 0000000000000004