rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=b3a/1/0x4000000000000004 softirq=262486/262487 fqs=0 (t=10501 jiffies g=441761 q=114) rcu: rcu_preempt kthread starved for 10502 jiffies! g441761 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt I28968 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3386 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4082 schedule+0xdc/0x2b0 kernel/sched/core.c:4156 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1658 [inline] rcu_gp_kthread+0xa10/0x1940 kernel/rcu/tree.c:1818 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 5289 Comm: syz-executor.1 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:475 [inline] check_cpu_stall kernel/rcu/tree_stall.h:549 [inline] rcu_pending kernel/rcu/tree.c:3030 [inline] rcu_sched_clock_irq.cold+0x51a/0xc37 kernel/rcu/tree.c:2276 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:171 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1314 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1144 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x4f/0x80 kernel/locking/spinlock.c:199 Code: c0 c8 b0 b3 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d 52 de c4 01 00 74 20 fb 66 0f 1f 44 00 00 01 00 00 00 e8 07 02 62 f9 65 8b 05 f8 4b 13 78 85 c0 74 06 41 RSP: 0018:ffffc90000007dd0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1367619 RBX: ffffffff86511890 RCX: 0000000000000003 RDX: dffffc0000000000 RSI: ffff88804897ebe8 RDI: ffff88804897eb94 RBP: ffffc90000007dd8 R08: 1ffffffff16a3372 R09: fffffbfff16a3373 R10: fffffbfff16a3372 R11: ffffffff8b519b97 R12: ffff8880ae827400 R13: ffff8880491aa818 R14: ffff8880ae827400 R15: dffffc0000000000 expire_timers kernel/time/timer.c:1448 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6b1/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1146 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:102 [inline] RIP: 0010:__local_bh_enable_ip+0x18e/0x270 kernel/softirq.c:196 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 df 00 00 00 48 83 3d 57 37 6c 08 00 0f 84 8f 00 00 00 fb 66 0f 1f 44 00 00 <65> 8b 05 03 a5 ba 7e 85 c0 74 7f 5b 41 5c 41 5d 5d c3 80 3d 02 81 RSP: 0018:ffffc90005737b50 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1367619 RBX: 0000000000000201 RCX: 0000000000000007 RDX: dffffc0000000000 RSI: ffff88804897ebe8 RDI: ffff88804897eb94 RBP: ffffc90005737b68 R08: 1ffffffff16a3372 R09: fffffbfff16a3373 R10: fffffbfff16a3372 R11: ffffffff8b519b97 R12: ffffffff87728251 R13: ffff88804897e300 R14: ffffc90005737d28 R15: ffff8882181e60e8 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x2c/0x30 kernel/locking/spinlock.c:207 spin_unlock_bh include/linux/spinlock.h:383 [inline] nl80211_netlink_notify net/wireless/nl80211.c:16782 [inline] nl80211_netlink_notify+0x661/0x980 net/wireless/nl80211.c:16734 notifier_call_chain+0xc2/0x230 kernel/notifier.c:83 __blocking_notifier_call_chain kernel/notifier.c:284 [inline] __blocking_notifier_call_chain kernel/notifier.c:271 [inline] blocking_notifier_call_chain kernel/notifier.c:295 [inline] blocking_notifier_call_chain+0x94/0xb0 kernel/notifier.c:292 netlink_release+0xc9f/0x1c90 net/netlink/af_netlink.c:774 __sock_release+0xce/0x280 net/socket.c:605 sock_close+0x1e/0x30 net/socket.c:1283 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_32_irqs_on arch/x86/entry/common.c:352 [inline] do_fast_syscall_32+0xbbd/0xe16 arch/x86/entry/common.c:408 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f7fe39 Code: 1d 00 00 00 89 d3 5b 5e 5d c3 8b 04 24 c3 8b 1c 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5d79e5c EFLAGS: 00000292 ORIG_RAX: 0000000000000006 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 00000000f5d79ecc RDI: 0000000000000184 RBP: 00000000f5d7a168 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000