rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=fa8c/1/0x4000000000000000 softirq=67846/67847 fqs=2 (detected by 0, t=10504 jiffies, g=102273, q=98 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 20638 Comm: syz-executor.2 Not tainted 6.1.27-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:203 Code: e8 25 00 00 00 0f 0b 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d a8 26 c9 0c 48 89 de 5b e9 d7 74 55 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d 74 a6 78 7e 65 8b 15 75 a6 78 7e f7 c2 00 RSP: 0018:ffffc900001e0d20 EFLAGS: 00000086 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000010003 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff23a068d R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff8880b992a5c0 R14: ffff88803a348340 R15: dffffc0000000000 FS: 00007f61ed24e700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000440 CR3: 0000000079cd4000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] static_key_false include/linux/jump_label.h:207 [inline] trace_hrtimer_start include/trace/events/timer.h:198 [inline] debug_activate kernel/time/hrtimer.c:476 [inline] enqueue_hrtimer+0x3a/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1113 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [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 02 d4 54 f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 77 b8 d2 f6 65 8b 05 58 34 77 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc900115f78c0 EFLAGS: 00000206 RAX: fd3d184e4b000100 RBX: 1ffff920022bef1c RCX: ffffffff91a7a103 RDX: dffffc0000000000 RSI: ffffffff8aebd020 RDI: 0000000000000001 RBP: ffffc900115f7960 R08: dffffc0000000000 R09: ffffed1007214c12 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff920022bef18 R14: ffffc900115f78e0 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:405 [inline] timerfd_clock_was_set+0x1b3/0x2a0 fs/timerfd.c:113 clock_was_set+0x86e/0x900 kernel/time/hrtimer.c:980 timekeeping_inject_offset+0x65f/0x710 kernel/time/timekeeping.c:1395 do_adjtimex+0x511/0xaa0 kernel/time/timekeeping.c:2444 do_clock_adjtime kernel/time/posix-timers.c:1118 [inline] __do_sys_clock_adjtime kernel/time/posix-timers.c:1130 [inline] __se_sys_clock_adjtime kernel/time/posix-timers.c:1121 [inline] __x64_sys_clock_adjtime+0x1dc/0x290 kernel/time/posix-timers.c:1121 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f61ec48c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f61ed24e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000131 RAX: ffffffffffffffda RBX: 00007f61ec5ac050 RCX: 00007f61ec48c169 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007f61ec4e7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc764b788f R14: 00007f61ed24e300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10490 jiffies! g102273 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:26712 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x132c/0x4330 kernel/sched/core.c:6554 schedule+0xbf/0x180 kernel/sched/core.c:6630 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x2c2/0x1010 kernel/rcu/tree.c:1660 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1859 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted 6.1.27-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_many_cond+0x1f62/0x33d0 kernel/smp.c:987 Code: 2f 44 89 ee 83 e6 01 31 ff e8 5a 0c 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 e5 08 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff RSP: 0018:ffffc900000e75a0 EFLAGS: 00000293 RAX: ffffffff817ebffd RBX: 1ffff11017328021 RCX: ffff88813fe60000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900000e7980 R08: ffffffff817ebfc6 R09: fffffbfff2050445 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940108 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f04f83fcff8 CR3: 000000000cc8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1155 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1316 [inline] text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1516 text_poke_flush arch/x86/kernel/alternative.c:1707 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1714 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306