====================================================== WARNING: possible circular locking dependency detected 6.1.0-rc5-next-20221116 #1 Not tainted ------------------------------------------------------ syz-executor.0/16078 is trying to acquire lock: ffff88800b568400 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_bmap+0x52/0x470 but task is already holding lock: ffff8880101423f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48f/0xc10 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: mutex_lock_io_nested+0x14c/0x1330 __jbd2_log_wait_for_space+0x238/0x460 add_transaction_credits+0xa42/0xb80 start_this_handle+0x3ac/0x14c0 jbd2__journal_start+0x394/0x8d0 __ext4_journal_start_sb+0x395/0x470 ext4_dirty_inode+0xa1/0x110 __mark_inode_dirty+0x1aa/0xe70 generic_update_time+0x21b/0x2b0 file_update_time+0x22f/0x280 ext4_page_mkwrite+0x2ee/0x1a70 do_page_mkwrite+0x1a0/0x640 __handle_mm_fault+0x12ac/0x3640 handle_mm_fault+0x283/0x970 do_user_addr_fault+0x53a/0x1300 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 -> #2 (sb_pagefaults){.+.+}-{0:0}: ext4_page_mkwrite+0x1fc/0x1a70 do_page_mkwrite+0x1a0/0x640 __handle_mm_fault+0x12ac/0x3640 handle_mm_fault+0x283/0x970 do_user_addr_fault+0x53a/0x1300 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 -> #1 (&mm->mmap_lock){++++}-{3:3}: down_read+0x9c/0x450 do_user_addr_fault+0xb04/0x1300 exc_page_fault+0x9c/0x1a0 asm_exc_page_fault+0x26/0x30 fault_in_readable+0x1bb/0x2e0 fault_in_iov_iter_readable+0x256/0x2c0 generic_perform_write+0x1b4/0x580 ext4_buffered_write_iter+0x164/0x460 ext4_file_write_iter+0x3ff/0x1910 vfs_write+0xa4f/0xe40 ksys_write+0x12b/0x260 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc -> #0 (&sb->s_type->i_mutex_key#6){++++}-{3:3}: __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a6/0x530 down_read+0x9c/0x450 ext4_bmap+0x52/0x470 bmap+0xb0/0x130 jbd2_journal_bmap+0xac/0x190 jbd2_journal_flush+0x857/0xc10 __ext4_ioctl+0x9b0/0x4340 __x64_sys_ioctl+0x19e/0x210 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#6 --> sb_pagefaults --> &journal->j_checkpoint_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_checkpoint_mutex); lock(sb_pagefaults); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#6); *** DEADLOCK *** 2 locks held by syz-executor.0/16078: #0: ffff888010142170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x162/0x310 #1: ffff8880101423f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48f/0xc10 stack backtrace: CPU: 1 PID: 16078 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221116 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x8f/0xb7 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a6/0x530 down_read+0x9c/0x450 ext4_bmap+0x52/0x470 bmap+0xb0/0x130 jbd2_journal_bmap+0xac/0x190 jbd2_journal_flush+0x857/0xc10 __ext4_ioctl+0x9b0/0x4340 __x64_sys_ioctl+0x19e/0x210 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f194b47bb19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f19489f1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f194b58ef60 RCX: 00007f194b47bb19 RDX: 0000000020000080 RSI: 000000004004662b RDI: 0000000000000003 RBP: 00007f194b4d5f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffee92cd9bf R14: 00007f19489f1300 R15: 0000000000022000 tmpfs: Bad value for 'huge' kauditd_printk_skb: 1 callbacks suppressed audit: type=1400 audit(1668595521.504:34): avc: denied { block_suspend } for pid=16085 comm="syz-executor.7" capability=36 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 cgroup: fork rejected by pids controller in /syz1 warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow tmpfs: Bad value for 'huge' tmpfs: Bad value for 'huge' tmpfs: Bad value for 'huge' warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow Bluetooth: hci4: command 0x0406 tx timeout Bluetooth: hci4: link tx timeout Bluetooth: hci4: killing stalled connection 10:aa:aa:aa:aa:aa Bluetooth: hci4: link tx timeout Bluetooth: hci4: killing stalled connection 10:aa:aa:aa:aa:aa