rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=77bc/1/0x4000000000000000 softirq=5151/5152 fqs=0 rcu: (detected by 1, t=10502 jiffies, g=5041, q=6 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5095 Comm: syz-executor202 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x2e/0xb0 kernel/rcu/tree.c:700 Code: 41 57 41 56 53 65 ff 05 78 66 88 7e e8 eb e6 f8 09 89 c3 83 f8 08 73 7a 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd d0 e9 b0 8d <4c> 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 2c da 7c 00 RSP: 0018:ffffc90000007b60 EFLAGS: 00000093 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8171c080 RDX: 0000000000000000 RSI: ffffffff8bfed340 RDI: ffffffff8bfed300 RBP: ffffc90000007cb8 R08: ffffffff8f872cef R09: 1ffffffff1f0e59d R10: dffffc0000000000 R11: fffffbfff1f0e59e R12: 1ffff92000000f7c R13: ffffffff8903fb46 R14: ffffffff8db0e9d0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efcbdc3f130 CR3: 000000001e308000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0xbf/0x9d0 kernel/locking/lockdep.c:5765 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] snd_hrtimer_callback+0x2d6/0x380 sound/core/hrtimer.c:60 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x107/0x3a0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 fe 49 79 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 a3 f1 e5 f5 65 8b 05 f4 d5 84 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90003aef940 EFLAGS: 00000206 RAX: 79cf45b4635bff00 RBX: 1ffff9200075df2c RCX: ffffffff81720c2a RDX: dffffc0000000000 RSI: ffffffff8baac1e0 RDI: 0000000000000001 RBP: ffffc90003aef9d0 R08: ffffffff92ce1587 R09: 1ffffffff259c2b0 R10: dffffc0000000000 R11: fffffbfff259c2b1 R12: dffffc0000000000 R13: 1ffff9200075df28 R14: ffffc90003aef960 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] snd_timer_stop1+0x7d9/0x930 sound/core/timer.c:660 snd_timer_stop sound/core/timer.c:710 [inline] snd_timer_close_locked+0x217/0x8c0 sound/core/timer.c:408 snd_timer_close sound/core/timer.c:463 [inline] snd_timer_user_release+0x129/0x2d0 sound/core/timer.c:1524 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 __do_sys_exit_group kernel/exit.c:1038 [inline] __se_sys_exit_group kernel/exit.c:1036 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7efcbdbc2df9 Code: Unable to access opcode bytes at 0x7efcbdbc2dcf. RSP: 002b:00007ffc276a9d98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007efcbdbc2df9 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007efcbdc3e2b0 R08: ffffffffffffffb8 R09: 00000000000000a0 R10: 00000000000000a0 R11: 0000000000000246 R12: 00007efcbdc3e2b0 R13: 0000000000000000 R14: 00007efcbdc3ed20 R15: 00007efcbdb93fa0 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.534 msecs rcu: rcu_preempt kthread starved for 10502 jiffies! g5041 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:24656 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x17d3/0x4a20 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 10 Comm: kworker/u8:0 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x1850/0x2960 kernel/smp.c:855 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 d9 d5 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 84 d1 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 68 d1 RSP: 0018:ffffc900000f76e0 EFLAGS: 00000293 RAX: ffffffff818923e8 RBX: 1ffff11017288be5 RCX: ffff888016ea9e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900000f78e0 R08: ffffffff818923b7 R09: 1ffffffff259c2a0 R10: dffffc0000000000 R11: fffffbfff259c2a1 R12: dffffc0000000000 R13: ffff8880b9445f28 R14: ffff8880b953f480 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efcbdc3f130 CR3: 000000000df32000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2086 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2296 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2494 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243