rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=21b/1/0x4000000000000000 softirq=52927/52928 fqs=5087 
	(t=10500 jiffies g=92801 q=673)
NMI backtrace for cpu 1
CPU: 1 PID: 1228 Comm: aoe_tx0 Not tainted 5.16.0-rc4-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+0x9d/0x746 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:handle_tx+0x138/0x610 drivers/net/caif/caif_serial.c:225
Code: 8b 63 30 4c 39 64 24 10 0f 84 95 02 00 00 e8 5f 85 93 fc 4d 85 e4 0f 84 87 02 00 00 e8 51 85 93 fc 49 8d 44 24 70 48 89 04 24 <48> c1 e8 03 0f b6 04 28 84 c0 74 08 3c 03 0f 8e d9 03 00 00 4c 89
RSP: 0000:ffffc900053b7b20 EFLAGS: 00000293
RAX: ffff888075a56b30 RBX: ffff888070e4ac80 RCX: 0000000000000000
RDX: ffff88801dd56140 RSI: ffffffff84e35f8f RDI: 0000000000000003
RBP: dffffc0000000000 R08: 0000000000000000 R09: 00000000471c0b00
R10: ffffffff84e361dc R11: 0000000000000000 R12: ffff888075a56ac0
R13: ffff88801e206000 R14: 0000000000000020 R15: ffff888070e4a000
 __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:	8b 63 30             	mov    0x30(%rbx),%esp
   3:	4c 39 64 24 10       	cmp    %r12,0x10(%rsp)
   8:	0f 84 95 02 00 00    	je     0x2a3
   e:	e8 5f 85 93 fc       	callq  0xfc938572
  13:	4d 85 e4             	test   %r12,%r12
  16:	0f 84 87 02 00 00    	je     0x2a3
  1c:	e8 51 85 93 fc       	callq  0xfc938572
  21:	49 8d 44 24 70       	lea    0x70(%r12),%rax
  26:	48 89 04 24          	mov    %rax,(%rsp)
* 2a:	48 c1 e8 03          	shr    $0x3,%rax <-- trapping instruction
  2e:	0f b6 04 28          	movzbl (%rax,%rbp,1),%eax
  32:	84 c0                	test   %al,%al
  34:	74 08                	je     0x3e
  36:	3c 03                	cmp    $0x3,%al
  38:	0f 8e d9 03 00 00    	jle    0x417
  3e:	4c                   	rex.WR
  3f:	89                   	.byte 0x89