rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=d8e/1/0x4000000000000002 softirq=12194/12194 fqs=11 
	(t=10501 jiffies g=6237 q=590)
rcu: rcu_preempt kthread starved for 10479 jiffies! g6237 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    28992    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8182 Comm: syz-executor.0 Not tainted 5.4.0-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:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x31/0x50 kernel/kcov.c:107
Code: 0c 25 c0 1d 02 00 65 8b 15 38 84 8b 7e f7 c2 00 01 1f 00 75 2c 8b 91 80 13 00 00 83 fa 02 75 21 48 8b 91 88 13 00 00 48 8b 32 <48> 8d 7e 01 8b 89 84 13 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89
RSP: 0018:ffffc90002257740 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81487326 RBX: ffffea00029cb240 RCX: ffff888097dc6040
RDX: ffffc90001ec9000 RSI: 000000000003ffff RDI: ffffea00029cb240
RBP: ffffc90002257768 R08: dffffc0000000000 R09: fffffbfff120248a
R10: fffffbfff120248a R11: 0000000000000000 R12: ffff888092a867a0
R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff88809f47b728
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_common kernel/sched/core.c:4236 [inline]
 preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261
 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50
 __lru_cache_add+0x23b/0x290 mm/swap.c:412
 lru_cache_add_anon+0x1bf/0x230 mm/swap.c:423
 shmem_getpage_gfp+0x185b/0x2f80 mm/shmem.c:1885
 shmem_getpage mm/shmem.c:154 [inline]
 shmem_write_begin+0xcb/0x1b0 mm/shmem.c:2487
 generic_perform_write+0x25d/0x4e0 mm/filemap.c:3309
 __generic_file_write_iter+0x235/0x500 mm/filemap.c:3438
 generic_file_write_iter+0x48e/0x630 mm/filemap.c:3470
 call_write_iter include/linux/fs.h:1902 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0x5a1/0x740 fs/read_write.c:496
 vfs_write+0x275/0x590 fs/read_write.c:558
 ksys_pwrite64 fs/read_write.c:665 [inline]
 __do_sys_pwrite64 fs/read_write.c:675 [inline]
 __se_sys_pwrite64 fs/read_write.c:672 [inline]
 __x64_sys_pwrite64+0x162/0x1d0 fs/read_write.c:672
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x414477
Code: 12 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 a1 18 00 00 c3 48 83 ec 08 e8 a7 f9 ff ff 48 89 04 24 49 89 ca b8 12 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 ed f9 ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f5f35d87a80 EFLAGS: 00000293 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 0000000020000290 RCX: 0000000000414477
RDX: 0000000008100000 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 0000000000000000 R08: fe03f80fe03f80ff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00000000004cab3e R14: 00000000004e3fc0 R15: 00000000ffffffff