rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=1f34/1/0x4000000000000000 softirq=63318/63319 fqs=1 rcu: (detected by 1, t=10505 jiffies, g=99997, q=109 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 21898 Comm: syz-executor.0 Not tainted 6.6.0-rc2-syzkaller-00278-gdc912ba91b7e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 RIP: 0010:__lock_acquire+0xe9d/0x5de0 kernel/locking/lockdep.c:5008 Code: 00 00 e9 01 02 00 00 44 89 eb 0f 87 8f 33 00 00 49 8d 7c da 08 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 <0f> 85 af 31 00 00 49 8b 5c da 08 48 85 db 0f 85 9c f2 ff ff e9 74 RSP: 0018:ffffc90000007b20 EFLAGS: 00000046 RAX: ffff888035806040 RBX: 0000000000000000 RCX: 1ffff11005609e61 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88802b04f308 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001 R10: ffff88802b04f300 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fd03430b6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd03430bd58 CR3: 0000000040a98000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd5/0xc60 net/sched/sch_taprio.c:935 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline] __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 e6 86 26 f7 48 89 df e8 de 05 27 f7 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f 01 00 00 00 e8 d5 6f 18 f7 65 8b 05 96 c4 c2 75 85 c0 74 12 5b RSP: 0018:ffffc90004e3fa78 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff8880b982b940 RCX: 1ffffffff233c916 RDX: 0000000000000000 RSI: ffffffff8a8c9ba0 RDI: ffffffff8ae90ce0 RBP: 0000000000000282 R08: 0000000000000001 R09: fffffbfff233c7d0 R10: ffffffff919e3e87 R11: 0000000000000002 R12: fe232be91ff57acd R13: 0000000000000000 R14: 000002391ff57acd R15: dffffc0000000000 clock_was_set+0x592/0x850 kernel/time/hrtimer.c:972 timekeeping_inject_offset+0x4d1/0x640 kernel/time/timekeeping.c:1395 do_adjtimex+0x373/0xaa0 kernel/time/timekeeping.c:2444 do_clock_adjtime kernel/time/posix-timers.c:1159 [inline] __do_sys_clock_adjtime+0x173/0x280 kernel/time/posix-timers.c:1171 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd03367cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd03430b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000131 RAX: ffffffffffffffda RBX: 00007fd03379c050 RCX: 00007fd03367cae9 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007fd0336c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fd03379c050 R15: 00007ffc8750c5a8 rcu: rcu_preempt kthread starved for 10500 jiffies! g99997 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:27480 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x5a10 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613 rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 16105 Comm: kworker/u4:1 Not tainted 6.6.0-rc2-syzkaller-00278-gdc912ba91b7e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:300 [inline] RIP: 0010:smp_call_function_many_cond+0x4db/0x1570 kernel/smp.c:844 Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 fc 4c 89 fd 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 fc 8a 0b 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 3c 0e 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc90004787920 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b98414c0 RCX: 0000000000000000 RDX: ffff888034b0a1c0 RSI: ffffffff817b3914 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 1ffffffff1976571 R12: ffffed1017308299 R13: 0000000000000001 R14: ffff8880b993d900 R15: ffff8880b98414c8 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0012df000 CR3: 000000000c976000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1012 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1998 [inline] text_poke_bp_batch+0x2ce/0x960 arch/x86/kernel/alternative.c:2208 text_poke_flush arch/x86/kernel/alternative.c:2399 [inline] text_poke_flush arch/x86/kernel/alternative.c:2396 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2406 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32e/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:830 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304