======================================================
WARNING: possible circular locking dependency detected
6.2.0-syzkaller-13216-gc4d3b488a90b #0 Not tainted
------------------------------------------------------
syz-executor.3/1941 is trying to acquire lock:
ffff88814b7543f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x238/0x4b0 fs/jbd2/checkpoint.c:110
but task is already holding lock:
ffff8880347f8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880347f8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 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+0x3d/0x50 kernel/locking/rwsem.c:1520
inode_lock_shared include/linux/fs.h:768 [inline]
ext4_bmap+0x52/0x470 fs/ext4/inode.c:3242
bmap+0xae/0x120 fs/inode.c:1799
jbd2_journal_bmap+0xac/0x1c0 fs/jbd2/journal.c:976
__jbd2_journal_erase fs/jbd2/journal.c:1788 [inline]
jbd2_journal_flush+0x87b/0xc90 fs/jbd2/journal.c:2491
ext4_ioctl_checkpoint fs/ext4/ioctl.c:1082 [inline]
__ext4_ioctl+0xb3f/0x4c90 fs/ext4/ioctl.c:1590
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
-> #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+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056
lock_acquire kernel/locking/lockdep.c:5669 [inline]
lock_acquire+0x1e3/0x670 kernel/locking/lockdep.c:5634
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
mutex_lock_io_nested+0x143/0x11a0 kernel/locking/mutex.c:833
__jbd2_log_wait_for_space+0x238/0x4b0 fs/jbd2/checkpoint.c:110
add_transaction_credits+0xa2d/0xb70 fs/jbd2/transaction.c:298
start_this_handle+0x3ae/0x14e0 fs/jbd2/transaction.c:422
jbd2__journal_start+0x39d/0x9d0 fs/jbd2/transaction.c:520
__ext4_journal_start_sb+0x706/0x890 fs/ext4/ext4_jbd2.c:111
__ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
ext4_dirty_inode+0xa5/0x130 fs/ext4/inode.c:6107
__mark_inode_dirty+0x247/0x1250 fs/fs-writeback.c:2421
mark_inode_dirty include/linux/fs.h:2127 [inline]
generic_write_end+0x354/0x440 fs/buffer.c:2227
ext4_da_write_end+0x1f5/0xa50 fs/ext4/inode.c:3174
generic_perform_write+0x316/0x570 mm/filemap.c:3937
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285
ext4_file_write_iter+0x8bf/0x1710 fs/ext4/file.c:700
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:885 [inline]
dump_user_range+0x234/0x700 fs/coredump.c:912
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2d28/0x3cc0 fs/coredump.c:762
get_signal+0x1bff/0x25b0 kernel/signal.c:2845
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:309
exc_page_fault+0xc0/0x170 arch/x86/mm/fault.c:1557
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
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-executor.3/1941:
#0: ffff88814b750460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1bff/0x25b0 kernel/signal.c:2845
#1: ffff8880347f8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff8880347f8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:279
stack backtrace:
CPU: 0 PID: 1941 Comm: syz-executor.3 Not tainted 6.2.0-syzkaller-13216-gc4d3b488a90b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
check_noncircular+0x25f/0x2e0 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+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056
lock_acquire kernel/locking/lockdep.c:5669 [inline]
lock_acquire+0x1e3/0x670 kernel/locking/lockdep.c:5634
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
mutex_lock_io_nested+0x143/0x11a0 kernel/locking/mutex.c:833
__jbd2_log_wait_for_space+0x238/0x4b0 fs/jbd2/checkpoint.c:110
add_transaction_credits+0xa2d/0xb70 fs/jbd2/transaction.c:298
start_this_handle+0x3ae/0x14e0 fs/jbd2/transaction.c:422
jbd2__journal_start+0x39d/0x9d0 fs/jbd2/transaction.c:520
__ext4_journal_start_sb+0x706/0x890 fs/ext4/ext4_jbd2.c:111
__ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
ext4_dirty_inode+0xa5/0x130 fs/ext4/inode.c:6107
__mark_inode_dirty+0x247/0x1250 fs/fs-writeback.c:2421
mark_inode_dirty include/linux/fs.h:2127 [inline]
generic_write_end+0x354/0x440 fs/buffer.c:2227
ext4_da_write_end+0x1f5/0xa50 fs/ext4/inode.c:3174
generic_perform_write+0x316/0x570 mm/filemap.c:3937
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285
ext4_file_write_iter+0x8bf/0x1710 fs/ext4/file.c:700
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:885 [inline]
dump_user_range+0x234/0x700 fs/coredump.c:912
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2d28/0x3cc0 fs/coredump.c:762
get_signal+0x1bff/0x25b0 kernel/signal.c:2845
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:309
exc_page_fault+0xc0/0x170 arch/x86/mm/fault.c:1557
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x6438bd01
Code: Unable to access opcode bytes at 0x6438bcd7.
RSP: 002b:0000000020000518 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f5ebafabf80 RCX: 00007f5ebae8c169
RDX: 0000000020000340 RSI: 0000000020000510 RDI: 0000000000200000
RBP: 00007f5ebaee7ca1 R08: 0000000020000580 R09: 0000000020000580
R10: 0000000020000540 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffd8decaaef R14: 00007f5ebbbad300 R15: 0000000000022000
</TASK>