device lo left promiscuous mode
device lo entered promiscuous mode
device lo left promiscuous mode
======================================================
WARNING: possible circular locking dependency detected
6.2.0-rc6-next-20230202 #1 Not tainted
------------------------------------------------------
rs:main Q:Reg/165 is trying to acquire lock:
ffff88800ff003f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x238/0x4b0

but task is already holding lock:
ffff888016a55380 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#6){++++}-{3:3}:
       down_read+0x3d/0x50
       ext4_bmap+0x52/0x470
       bmap+0xb0/0x130
       jbd2_journal_bmap+0xac/0x1d0
       jbd2_journal_flush+0x87f/0xc90
       __ext4_ioctl+0x9fd/0x4330
       __x64_sys_ioctl+0x19e/0x210
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

-> #0 (&journal->j_checkpoint_mutex){+.+.}-{3:3}:
       __lock_acquire+0x2da7/0x63b0
       lock_acquire.part.0+0xec/0x320
       mutex_lock_io_nested+0x149/0x1300
       __jbd2_log_wait_for_space+0x238/0x4b0
       add_transaction_credits+0xa42/0xb80
       start_this_handle+0x3a6/0x14d0
       jbd2__journal_start+0x394/0x6b0
       __ext4_journal_start_sb+0x4c2/0x6f0
       ext4_dirty_inode+0xa5/0x130
       __mark_inode_dirty+0x1aa/0xee0
       generic_update_time+0x21b/0x2b0
       file_modified_flags+0x2d4/0x330
       ext4_buffered_write_iter+0xf9/0x460
       ext4_file_write_iter+0x3ff/0x1930
       vfs_write+0x9b4/0xdc0
       ksys_write+0x12b/0x260
       do_syscall_64+0x3f/0x90
       entry_SYSCALL_64_after_hwframe+0x72/0xdc

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#6);
                               lock(&journal->j_checkpoint_mutex);
                               lock(&sb->s_type->i_mutex_key#6);
  lock(&journal->j_checkpoint_mutex);

 *** DEADLOCK ***

3 locks held by rs:main Q:Reg/165:
 #0: ffff88800cb58868 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xeb/0x110
 #1: ffff88800fef4438 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x12b/0x260
 #2: ffff888016a55380 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460

stack backtrace:
CPU: 1 PID: 165 Comm: rs:main Q:Reg Not tainted 6.2.0-rc6-next-20230202 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 check_noncircular+0x263/0x2e0
 __lock_acquire+0x2da7/0x63b0
 lock_acquire.part.0+0xec/0x320
 mutex_lock_io_nested+0x149/0x1300
 __jbd2_log_wait_for_space+0x238/0x4b0
 add_transaction_credits+0xa42/0xb80
 start_this_handle+0x3a6/0x14d0
 jbd2__journal_start+0x394/0x6b0
 __ext4_journal_start_sb+0x4c2/0x6f0
 ext4_dirty_inode+0xa5/0x130
 __mark_inode_dirty+0x1aa/0xee0
 generic_update_time+0x21b/0x2b0
 file_modified_flags+0x2d4/0x330
 ext4_buffered_write_iter+0xf9/0x460
 ext4_file_write_iter+0x3ff/0x1930
 vfs_write+0x9b4/0xdc0
 ksys_write+0x12b/0x260
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f1f36aebfef
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 29 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 5c fd ff ff 48
RSP: 002b:00007f1f35ca7860 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1f2c021b20 RCX: 00007f1f36aebfef
RDX: 0000000000000051 RSI: 00007f1f2c021dc0 RDI: 0000000000000007
RBP: 0000000000000051 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f1f2c021dc0
R13: 0000000000000000 R14: 0000000000000051 R15: 00007f1f2c021b20
 </TASK>
device lo left promiscuous mode
device lo entered promiscuous mode
device lo entered promiscuous mode
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
ieee80211 phy84: Selected rate control algorithm 'minstrel_ht'
ieee80211 phy85: Selected rate control algorithm 'minstrel_ht'
mmap: syz-executor.0 (16699) uses deprecated remap_file_pages() syscall. See Documentation/mm/remap_file_pages.rst.
ieee80211 phy86: Selected rate control algorithm 'minstrel_ht'
ieee80211 phy87: Selected rate control algorithm 'minstrel_ht'
EXT4-fs (sda): re-mounted 7b5d9a40-9011-49ec-8035-27953f97a4d8. Quota mode: writeback.
EXT4-fs (sda): re-mounted 7b5d9a40-9011-49ec-8035-27953f97a4d8. Quota mode: writeback.
EXT4-fs (sda): re-mounted 7b5d9a40-9011-49ec-8035-27953f97a4d8. Quota mode: writeback.
ieee80211 phy88: Selected rate control algorithm 'minstrel_ht'
EXT4-fs (sda): re-mounted 7b5d9a40-9011-49ec-8035-27953f97a4d8. Quota mode: writeback.
ieee80211 phy89: Selected rate control algorithm 'minstrel_ht'
EXT4-fs (sda): re-mounted 7b5d9a40-9011-49ec-8035-27953f97a4d8. Quota mode: writeback.
ieee80211 phy90: Selected rate control algorithm 'minstrel_ht'
ieee80211 phy91: Selected rate control algorithm 'minstrel_ht'
ieee80211 phy92: Selected rate control algorithm 'minstrel_ht'
Zero length message leads to an empty skb
netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 'syz-executor.4': attribute type 1 has an invalid length.