====================================================== WARNING: possible circular locking dependency detected 6.2.0-syzkaller-18295-ga9b06ec42c0f #0 Not tainted ------------------------------------------------------ syz-executor308/15533 is trying to acquire lock: ffff0000d8d163f8 (&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: ffff0000e062d440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] ffff0000e062d440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0x9c/0x538 fs/ext4/file.c:279 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:1509 inode_lock_shared include/linux/fs.h:766 [inline] ext4_bmap+0x58/0x35c fs/ext4/inode.c:3243 bmap+0xa8/0xe8 fs/inode.c:1798 jbd2_journal_bmap fs/jbd2/journal.c:977 [inline] __jbd2_journal_erase fs/jbd2/journal.c:1789 [inline] jbd2_journal_flush+0x4c0/0xa60 fs/jbd2/journal.c:2492 ext4_ioctl_checkpoint fs/ext4/ioctl.c:1082 [inline] __ext4_ioctl fs/ext4/ioctl.c:1590 [inline] ext4_ioctl+0x38b0/0x6eec fs/ext4/ioctl.c:1610 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:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5055 lock_acquire+0x2e8/0x8c0 kernel/locking/lockdep.c:5668 __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+0x598/0xd54 fs/ext4/ext4_jbd2.c:111 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0xa0/0x104 fs/ext4/inode.c:6107 __mark_inode_dirty+0x460/0x18b4 fs/fs-writeback.c:2419 mark_inode_dirty include/linux/fs.h:2465 [inline] generic_write_end+0x15c/0x414 fs/buffer.c:2184 ext4_da_write_end+0x680/0x9fc fs/ext4/inode.c:3175 generic_perform_write+0x384/0x55c mm/filemap.c:3784 ext4_buffered_write_iter+0x2e0/0x538 fs/ext4/file.c:285 ext4_file_write_iter+0x188/0x16c0 __kernel_write_iter+0x264/0x5f8 fs/read_write.c:517 __kernel_write+0x11c/0x174 fs/read_write.c:537 __dump_emit fs/coredump.c:811 [inline] dump_emit+0x248/0x358 fs/coredump.c:848 writenote+0x150/0x334 fs/binfmt_elf.c:1481 write_note_info fs/binfmt_elf.c:1967 [inline] elf_core_dump+0x2aa8/0x3640 fs/binfmt_elf.c:2124 do_coredump+0x14d4/0x22dc fs/coredump.c:762 get_signal+0xfe8/0x159c kernel/signal.c:2845 do_signal arch/arm64/kernel/signal.c:1246 [inline] do_notify_resume+0x338/0x3c90 arch/arm64/kernel/signal.c:1299 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_da+0xb8/0x184 arch/arm64/kernel/entry-common.c:516 el0t_64_sync_handler+0xcc/0xf0 arch/arm64/kernel/entry-common.c:658 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 *** 2 locks held by syz-executor308/15533: #0: ffff0000d8d10460 (sb_writers#3){.+.+}-{0:0}, at: do_coredump+0x14b4/0x22dc fs/coredump.c:761 #1: ffff0000e062d440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #1: ffff0000e062d440 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0x9c/0x538 fs/ext4/file.c:279 stack backtrace: CPU: 0 PID: 15533 Comm: syz-executor308 Not tainted 6.2.0-syzkaller-18295-ga9b06ec42c0f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 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:2055 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5055 lock_acquire+0x2e8/0x8c0 kernel/locking/lockdep.c:5668 __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+0x598/0xd54 fs/ext4/ext4_jbd2.c:111 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline] ext4_dirty_inode+0xa0/0x104 fs/ext4/inode.c:6107 __mark_inode_dirty+0x460/0x18b4 fs/fs-writeback.c:2419 mark_inode_dirty include/linux/fs.h:2465 [inline] generic_write_end+0x15c/0x414 fs/buffer.c:2184 ext4_da_write_end+0x680/0x9fc fs/ext4/inode.c:3175 generic_perform_write+0x384/0x55c mm/filemap.c:3784 ext4_buffered_write_iter+0x2e0/0x538 fs/ext4/file.c:285 ext4_file_write_iter+0x188/0x16c0 __kernel_write_iter+0x264/0x5f8 fs/read_write.c:517 __kernel_write+0x11c/0x174 fs/read_write.c:537 __dump_emit fs/coredump.c:811 [inline] dump_emit+0x248/0x358 fs/coredump.c:848 writenote+0x150/0x334 fs/binfmt_elf.c:1481 write_note_info fs/binfmt_elf.c:1967 [inline] elf_core_dump+0x2aa8/0x3640 fs/binfmt_elf.c:2124 do_coredump+0x14d4/0x22dc fs/coredump.c:762 get_signal+0xfe8/0x159c kernel/signal.c:2845 do_signal arch/arm64/kernel/signal.c:1246 [inline] do_notify_resume+0x338/0x3c90 arch/arm64/kernel/signal.c:1299 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_da+0xb8/0x184 arch/arm64/kernel/entry-common.c:516 el0t_64_sync_handler+0xcc/0xf0 arch/arm64/kernel/entry-common.c:658 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591