warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow ====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc1-next-20220819 #1 Not tainted ------------------------------------------------------ syz-executor.4/4050 is trying to acquire lock: ffff88800bd48400 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_bmap+0x4e/0x470 but task is already holding lock: ffff88800fe203f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48b/0xc00 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+0x148/0x1310 jbd2_journal_flush+0x19a/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&journal->j_barrier){+.+.}-{3:3}: __mutex_lock+0x136/0x14d0 jbd2_journal_lock_updates+0x15e/0x310 ext4_change_inode_journal_flag+0x17f/0x530 ext4_fileattr_set+0x140d/0x18a0 vfs_fileattr_set+0x77c/0xb80 do_vfs_ioctl+0xfc2/0x1610 __x64_sys_ioctl+0x10c/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&sbi->s_writepages_rwsem){++++}-{0:0}: percpu_down_write+0x4d/0x3d0 ext4_ind_migrate+0x237/0x830 ext4_fileattr_set+0x1434/0x18a0 vfs_fileattr_set+0x77c/0xb80 do_vfs_ioctl+0xfc2/0x1610 __x64_sys_ioctl+0x10c/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&sb->s_type->i_mutex_key#6){++++}-{3:3}: __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 down_read+0x98/0x450 ext4_bmap+0x4e/0x470 bmap+0xac/0x120 jbd2_journal_bmap+0xa8/0x180 jbd2_journal_flush+0x853/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#6 --> &journal->j_barrier --> &journal->j_checkpoint_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_checkpoint_mutex); lock(&journal->j_barrier); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#6); *** DEADLOCK *** 2 locks held by syz-executor.4/4050: #0: ffff88800fe20170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x15e/0x310 #1: ffff88800fe203f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48b/0xc00 stack backtrace: CPU: 1 PID: 4050 Comm: syz-executor.4 Not tainted 6.0.0-rc1-next-20220819 #1 BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1521 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 4050, name: syz-executor.4 preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. irq event stamp: 2995 hardirqs last enabled at (2995): [] finish_task_switch.isra.0+0x22d/0x8a0 hardirqs last disabled at (2994): [] __schedule+0x11d7/0x2490 softirqs last enabled at (2778): [] __irq_exit_rcu+0x11b/0x180 softirqs last disabled at (2773): [] __irq_exit_rcu+0x11b/0x180 CPU: 1 PID: 4050 Comm: syz-executor.4 Not tainted 6.0.0-rc1-next-20220819 #1 syz-executor.4[4050] cmdline: /syz-executor.4 exec Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 __might_resched.cold+0x222/0x26b down_read_killable+0x75/0x490 __access_remote_vm+0xac/0x6f0 get_mm_cmdline.part.0+0x214/0x600 get_task_cmdline_kernel+0x1e9/0x230 dump_stack_print_cmdline.part.0+0x82/0x150 dump_stack_print_info+0x185/0x190 dump_stack_lvl+0x7f/0xb3 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 down_read+0x98/0x450 ext4_bmap+0x4e/0x470 bmap+0xac/0x120 jbd2_journal_bmap+0xa8/0x180 jbd2_journal_flush+0x853/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f76004d8b19 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:00007f75fda2d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f76005ec020 RCX: 00007f76004d8b19 RDX: 0000000020000340 RSI: 000000004004662b RDI: 0000000000000006 RBP: 00007f7600532f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0347ad6f R14: 00007f75fda2d300 R15: 0000000000022000 syz-executor.4[4050] cmdline: /syz-executor.4 exec Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 down_read+0x98/0x450 ext4_bmap+0x4e/0x470 bmap+0xac/0x120 jbd2_journal_bmap+0xa8/0x180 jbd2_journal_flush+0x853/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f76004d8b19 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:00007f75fda2d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f76005ec020 RCX: 00007f76004d8b19 RDX: 0000000020000340 RSI: 000000004004662b RDI: 0000000000000006 RBP: 00007f7600532f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff0347ad6f R14: 00007f75fda2d300 R15: 0000000000022000 loop1: detected capacity change from 0 to 264192 loop6: detected capacity change from 0 to 264192 nfs: Unknown parameter '//' isofs_fill_super: get root inode failed