rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10500 ticks this GP) idle=b3b/1/0x4000000000000000 softirq=127197/127197 fqs=5202 
	(t=10502 jiffies g=270333 q=1595)
NMI backtrace for cpu 1
CPU: 1 PID: 20853 Comm: syz-executor.2 Not tainted 5.15.0-rc7-next-20211027-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3922 [inline]
 rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2620
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x7/0x60 kernel/kcov.c:200
Code: 46 00 5d be 03 00 00 00 e9 a6 1b 33 02 66 0f 1f 44 00 00 48 8b be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 65 8b 05 f9 c2 8a 7e <89> c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 40 70 02 00 a9
RSP: 0018:ffffc90019f4fd40 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000000000000be RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888097083a80 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff86dd920a R11: 0000000000000004 R12: ffffc90019f4fdc0
R13: ffff88806dde2000 R14: 000000000000001c R15: 000000007f03c76c
 snd_seq_write+0x322/0x690 sound/core/seq/seq_clientmgr.c:1097
 vfs_write+0x28e/0xae0 fs/read_write.c:588
 ksys_write+0x1ee/0x250 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f670820ba39
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:00007f6705781188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f670830ef60 RCX: 00007f670820ba39
RDX: 00000000fffffee4 RSI: 00000000200000c0 RDI: 0000000000000004
RBP: 00007f6708265e8f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd8eae3d6f R14: 00007f6705781300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	46 00 5d be          	rex.RX add %r11b,-0x42(%rbp)
   4:	03 00                	add    (%rax),%eax
   6:	00 00                	add    %al,(%rax)
   8:	e9 a6 1b 33 02       	jmpq   0x2331bb3
   d:	66 0f 1f 44 00 00    	nopw   0x0(%rax,%rax,1)
  13:	48 8b be b0 01 00 00 	mov    0x1b0(%rsi),%rdi
  1a:	e8 b4 ff ff ff       	callq  0xffffffd3
  1f:	31 c0                	xor    %eax,%eax
  21:	c3                   	retq
  22:	90                   	nop
  23:	65 8b 05 f9 c2 8a 7e 	mov    %gs:0x7e8ac2f9(%rip),%eax        # 0x7e8ac323
* 2a:	89 c1                	mov    %eax,%ecx <-- trapping instruction
  2c:	48 8b 34 24          	mov    (%rsp),%rsi
  30:	81 e1 00 01 00 00    	and    $0x100,%ecx
  36:	65 48 8b 14 25 40 70 	mov    %gs:0x27040,%rdx
  3d:	02 00
  3f:	a9                   	.byte 0xa9