rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=49b/1/0x4000000000000000 softirq=42353/42353 fqs=0 
	(t=10500 jiffies g=60013 q=779)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g60013 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=48571
rcu: rcu_preempt kthread starved for 10500 jiffies! g60013 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26200 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 1375 Comm: aoe_tx0 Not tainted 5.15.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:481
 print_cpu_stall kernel/rcu/tree_stall.h:625 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:711 [inline]
 rcu_pending kernel/rcu/tree.c:3911 [inline]
 rcu_sched_clock_irq+0xf21/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 12 bc a5 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e7 1a 33 f7 65 8b 05 78 56 de 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90005a87980 EFLAGS: 00000206
RAX: c39f8d2969b34e00 RBX: 1ffff92000b50f34 RCX: ffffffff8162ea18
RDX: dffffc0000000000 RSI: ffffffff8a8b0b60 RDI: 0000000000000001
RBP: ffffc90005a87a18 R08: dffffc0000000000 R09: fffffbfff1f79a5c
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000b50f30 R14: ffffc90005a879a0 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 uart_write_room+0x137/0x2e0 drivers/tty/serial/serial_core.c:603
 handle_tx+0x164/0x620 drivers/net/caif/caif_serial.c:226
 __netdev_start_xmit include/linux/netdevice.h:5018 [inline]
 netdev_start_xmit include/linux/netdevice.h:5032 [inline]
 xmit_one net/core/dev.c:3594 [inline]
 dev_hard_start_xmit+0x298/0x7a0 net/core/dev.c:3610
 __dev_queue_xmit+0x1cee/0x3230 net/core/dev.c:4225
 tx+0x64/0x100 drivers/block/aoe/aoenet.c:63
 kthread+0x234/0x440 drivers/block/aoe/aoecmd.c:1230
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 1375 Comm: aoe_tx0 Not tainted 5.15.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x223/0x390 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:3911 [inline]
 rcu_sched_clock_irq+0xf26/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 12 bc a5 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e7 1a 33 f7 65 8b 05 78 56 de 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90005a87980 EFLAGS: 00000206
RAX: c39f8d2969b34e00 RBX: 1ffff92000b50f34 RCX: ffffffff8162ea18
RDX: dffffc0000000000 RSI: ffffffff8a8b0b60 RDI: 0000000000000001
RBP: ffffc90005a87a18 R08: dffffc0000000000 R09: fffffbfff1f79a5c
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff92000b50f30 R14: ffffc90005a879a0 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 uart_write_room+0x137/0x2e0 drivers/tty/serial/serial_core.c:603
 handle_tx+0x164/0x620 drivers/net/caif/caif_serial.c:226
 __netdev_start_xmit include/linux/netdevice.h:5018 [inline]
 netdev_start_xmit include/linux/netdevice.h:5032 [inline]
 xmit_one net/core/dev.c:3594 [inline]
 dev_hard_start_xmit+0x298/0x7a0 net/core/dev.c:3610
 __dev_queue_xmit+0x1cee/0x3230 net/core/dev.c:4225
 tx+0x64/0x100 drivers/block/aoe/aoenet.c:63
 kthread+0x234/0x440 drivers/block/aoe/aoecmd.c:1230
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>