====================================================== WARNING: possible circular locking dependency detected 6.3.0-rc1-syzkaller-gfe15c26ee26e #0 Not tainted ------------------------------------------------------ syz-executor.4/2191 is trying to acquire lock: ffff0000d89d03f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x1a4/0x5cc fs/jbd2/checkpoint.c:110 but task is already holding lock: ffff000147658e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] ffff000147658e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd8/0x508 fs/namei.c:4239 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#8){++++}-{3:3}: down_read+0x5c/0x78 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:768 [inline] ext4_bmap+0x58/0x35c fs/ext4/inode.c:3242 bmap+0xa8/0xe8 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+0x4c0/0xa60 fs/jbd2/journal.c:2491 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1079 [inline] __ext4_ioctl fs/ext4/ioctl.c:1587 [inline] ext4_ioctl+0x3860/0x6f58 fs/ext4/ioctl.c:1607 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 -> #0 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056 lock_acquire+0x2f0/0x8c8 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 mutex_lock_io_nested+0x6c/0x88 kernel/locking/mutex.c:833 __jbd2_log_wait_for_space+0x1a4/0x5cc fs/jbd2/checkpoint.c:110 add_transaction_credits+0x7dc/0xafc fs/jbd2/transaction.c:298 start_this_handle+0x5c4/0x13ac fs/jbd2/transaction.c:422 jbd2__journal_start+0x298/0x544 fs/jbd2/transaction.c:520 __ext4_journal_start_sb+0x5d8/0xd94 fs/ext4/ext4_jbd2.c:111 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] __ext4_unlink+0x370/0x998 fs/ext4/namei.c:3240 ext4_unlink+0x2ec/0xb10 fs/ext4/namei.c:3299 vfs_unlink+0x2f0/0x508 fs/namei.c:4250 do_unlinkat+0x4c8/0x82c fs/namei.c:4316 __do_sys_unlinkat fs/namei.c:4359 [inline] __se_sys_unlinkat fs/namei.c:4352 [inline] __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4352 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#8); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#8); lock(&journal->j_checkpoint_mutex); *** DEADLOCK *** 3 locks held by syz-executor.4/2191: #0: ffff0000d89ca460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:394 #1: ffff00014765e850 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff00014765e850 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x2cc/0x82c fs/namei.c:4301 #2: ffff000147658e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff000147658e08 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd8/0x508 fs/namei.c:4239 stack backtrace: CPU: 1 PID: 2191 Comm: syz-executor.4 Not tainted 6.3.0-rc1-syzkaller-gfe15c26ee26e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2056 check_noncircular+0x2cc/0x378 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 kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056 lock_acquire+0x2f0/0x8c8 kernel/locking/lockdep.c:5669 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 mutex_lock_io_nested+0x6c/0x88 kernel/locking/mutex.c:833 __jbd2_log_wait_for_space+0x1a4/0x5cc fs/jbd2/checkpoint.c:110 add_transaction_credits+0x7dc/0xafc fs/jbd2/transaction.c:298 start_this_handle+0x5c4/0x13ac fs/jbd2/transaction.c:422 jbd2__journal_start+0x298/0x544 fs/jbd2/transaction.c:520 __ext4_journal_start_sb+0x5d8/0xd94 fs/ext4/ext4_jbd2.c:111 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] __ext4_unlink+0x370/0x998 fs/ext4/namei.c:3240 ext4_unlink+0x2ec/0xb10 fs/ext4/namei.c:3299 vfs_unlink+0x2f0/0x508 fs/namei.c:4250 do_unlinkat+0x4c8/0x82c fs/namei.c:4316 __do_sys_unlinkat fs/namei.c:4359 [inline] __se_sys_unlinkat fs/namei.c:4352 [inline] __arm64_sys_unlinkat+0xcc/0xfc fs/namei.c:4352 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591