rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=8a1/1/0x4000000000000000 softirq=126768/126769 fqs=5160 
	(t=10502 jiffies g=174733 q=2052)
NMI backtrace for cpu 1
CPU: 1 PID: 1231 Comm: aoe_tx0 Not tainted 5.16.0-rc7-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:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 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:627 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:711 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq.cold+0x5c/0x759 kernel/rcu/tree.c:2597
 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:preempt_count_sub+0x21/0x150 kernel/sched/core.c:5459
Code: 66 0f 1f 84 00 00 00 00 00 48 c7 c0 c0 89 4c 90 53 89 fb 48 ba 00 00 00 00 00 fc ff df 48 89 c1 83 e0 07 48 c1 e9 03 83 c0 03 <0f> b6 14 11 38 d0 7c 08 84 d2 0f 85 e4 00 00 00 8b 0d 89 6d fd 0e
RSP: 0018:ffffc90004f67aa8 EFLAGS: 00000206
RAX: 0000000000000003 RBX: 0000000000000001 RCX: 1ffffffff2099138
RDX: dffffc0000000000 RSI: 0000000000000202 RDI: 0000000000000001
RBP: ffffffff9079ed78 R08: 0000000000000001 R09: ffffffff8ff7ab27
R10: 0000000000000001 R11: 0000000000000001 R12: 00000000ffffffff
R13: ffff888076caf001 R14: 0000000000000020 R15: 0000000000000020
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x3d/0x70 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:404 [inline]
 uart_write_room+0x174/0x2f0 drivers/tty/serial/serial_core.c:611
 tty_write_room+0x61/0x80 drivers/tty/tty_ioctl.c:79
 handle_tx+0x159/0x610 drivers/net/caif/caif_serial.c:226
 __netdev_start_xmit include/linux/netdevice.h:4994 [inline]
 netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 xmit_one net/core/dev.c:3590 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606
 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229
 tx+0x68/0xb0 drivers/block/aoe/aoenet.c:63
 kthread+0x1e7/0x3b0 drivers/block/aoe/aoecmd.c:1230
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:	66 0f 1f 84 00 00 00 	nopw   0x0(%rax,%rax,1)
   7:	00 00
   9:	48 c7 c0 c0 89 4c 90 	mov    $0xffffffff904c89c0,%rax
  10:	53                   	push   %rbx
  11:	89 fb                	mov    %edi,%ebx
  13:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  1a:	fc ff df
  1d:	48 89 c1             	mov    %rax,%rcx
  20:	83 e0 07             	and    $0x7,%eax
  23:	48 c1 e9 03          	shr    $0x3,%rcx
  27:	83 c0 03             	add    $0x3,%eax
* 2a:	0f b6 14 11          	movzbl (%rcx,%rdx,1),%edx <-- trapping instruction
  2e:	38 d0                	cmp    %dl,%al
  30:	7c 08                	jl     0x3a
  32:	84 d2                	test   %dl,%dl
  34:	0f 85 e4 00 00 00    	jne    0x11e
  3a:	8b 0d 89 6d fd 0e    	mov    0xefd6d89(%rip),%ecx        # 0xefd6dc9