INFO: task syz.7.4119:31200 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.4119      state:D stack:27592 pid:31200 tgid:31199 ppid:27220  task_flags:0x400040 flags:0x00080802
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e8ff9ce59
RSP: 002b:00007f3e90e1a028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f3e90215fa0 RCX: 00007f3e8ff9ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f3e90215fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3e90216038 R14: 00007f3e90215fa0 R15: 00007ffed59afc08
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/0:3/994:
2 locks held by getty/5440:
 #0: ffff888112f100a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
2 locks held by syz-executor/5594:
2 locks held by kworker/u10:11/9248:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc900072a7c40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
2 locks held by kworker/u10:16/9260:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90009dd7c40 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
1 lock held by udevd/25012:
 #0: ffff88810a9c4350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.7.4119/31200:
 #0: ffff88810a9c4350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
3 locks held by kworker/u9:10/32476:
1 lock held by syz.0.4639/1663:
 #0: ffff88810a9c4350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
2 locks held by syz.9.5301/6192:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6192 Comm: syz.9.5301 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__lock_acquire+0x197b/0x2cf0
Code: 14 25 ff 0f 00 00 39 05 ef c5 9f 12 73 06 89 05 e7 c5 9f 12 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7 70 ae 82
RSP: 0018:ffffc9000a526c60 EFLAGS: 00000002
RAX: ffffffff96e872b8 RBX: 00000000000003fd RCX: 00000000000008f7
RDX: ffffffff96ced968 RSI: ffff88810eb00c30 RDI: 00000000000003fd
RBP: 087e0c5a35a28131 R08: ffffc9000a526c28 R09: 0000000000000020
R10: 0000000000000003 R11: ffffffff81a22370 R12: ffffffff96d8c208
R13: ffffffff93e74638 R14: ffff88810eb00000 R15: 00000000000008f6
FS:  00007f2b45a3f6c0(0000) GS:ffff88818dc84000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b45a1ed58 CR3: 000000001264c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350
 seqcount_lockdep_reader_access+0x55/0x100
 ktime_get+0x45/0x220
 clockevents_program_event+0x290/0x630
 __hrtimer_rearm_deferred+0x270/0x450
 irqentry_exit+0x6d5/0x760
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x221/0x350
Code: ff ff ff e8 01 2e 08 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 eb 08 98 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 90 23 0b 0a cc 48 8d 3d 98 97 92
RSP: 0018:ffffc9000a5270b0 EFLAGS: 00000282
RAX: 7ecdc7a104b97200 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000004d08b500 RSI: ffffffff8e223b69 RDI: ffffffff8c28cb60
RBP: ffffffff82230d5c R08: ffffffff82230d5c R09: ffffffff8ea9aee0
R10: dffffc0000000000 R11: fffff940001c0a01 R12: 0000000000000000
R13: ffffffff8ea9aee0 R14: 0000000000000001 R15: 0000000000000246
 fs_reclaim_acquire+0x98/0x100
 kmem_cache_alloc_noprof+0x40/0x650
 alloc_buffer_head+0x2a/0x270
 folio_alloc_buffers+0x19b/0x640
 create_empty_buffers+0x3a/0x530
 ext4_block_write_begin+0x579/0x1950
 ext4_da_write_begin+0x86a/0xd60
 generic_perform_write+0x2e2/0x8f0
 ext4_buffered_write_iter+0xce/0x3a0
 ext4_file_write_iter+0x298/0x1bf0
 iter_file_splice_write+0x9a1/0x10f0
 direct_splice_actor+0x101/0x160
 splice_direct_to_actor+0x53a/0xc70
 do_splice_direct+0x195/0x290
 do_sendfile+0x535/0x7d0
 __se_sys_sendfile64+0x144/0x1a0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2b44b9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2b45a3f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f2b44e16180 RCX: 00007f2b44b9ce59
RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000007
RBP: 00007f2b44c32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 000000000e3aa6ea R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2b44e16218 R14: 00007f2b44e16180 R15: 00007ffc3f0da468
 </TASK>
