INFO: task syz.3.245:6784 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.245       state:D stack:24800 pid:6784  tgid:6772  ppid:5851   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 sync_bdevs+0x1ac/0x340 block/bdev.c:1288
 ksys_sync+0xb9/0x150 fs/sync.c:105
 __ia32_sys_sync+0xe/0x20 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f753538ebe9
RSP: 002b:00007f753298d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f75355b6450 RCX: 00007f753538ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f75355b6450 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f75355b64e8 R14: 00007f75355b6450 R15: 00007fff0f5dd848
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf93/0xfe0 kernel/hung_task.c:491
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10333 Comm: syz.0.1191 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x3a/0xb0 kernel/rcu/tree.c:751
Code: e8 eb 33 d3 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 10 ed bd 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 1c b7 7c 00 48 c7 c3 98 7f a1 92 49 03 1e 48 89
RSP: 0018:ffffc9000dcc75a0 EFLAGS: 00000046
RAX: 1ffffffff1b7bda2 RBX: 0000000000000000 RCX: 85aed5b5458ec500
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: ffffffff819b8633 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1006a36001 R12: 0000000000000000
R13: ffff8880b8624008 R14: ffffffff8dbded10 R15: dffffc0000000000
FS:  00007fad5d0106c0(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000005000 CR3: 000000004d92e000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
 do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
 psi_write_begin+0xab/0x160 kernel/sched/psi.c:183
 psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
 psi_sched_switch kernel/sched/stats.h:220 [inline]
 __schedule+0x22e9/0x4cc0 kernel/sched/core.c:6955
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 snd_rawmidi_write+0x3a8/0xbd0 sound/core/rawmidi.c:1616
 do_loop_readv_writev fs/read_write.c:850 [inline]
 vfs_writev+0x4b6/0x960 fs/read_write.c:1059
 do_writev+0x14d/0x2d0 fs/read_write.c:1103
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad5c18ebe9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fad5d010038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fad5c3b5fa0 RCX: 00007fad5c18ebe9
RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000007
RBP: 00007fad5c211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad5c3b6038 R14: 00007fad5c3b5fa0 R15: 00007ffea6b22fe8
 </TASK>