rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=2ea4/1/0x4000000000000000 softirq=18352/18353 fqs=2 rcu: (detected by 1, t=10502 jiffies, g=25725, q=239 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5286 Comm: kworker/0:7 Not tainted 6.11.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_freezable_pwr_efficient sync_hw_clock RIP: 0010:check_wait_context kernel/locking/lockdep.c:4772 [inline] RIP: 0010:__lock_acquire+0x410/0x3cb0 kernel/locking/lockdep.c:5092 Code: fc ff df 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 80 2b 00 00 8b 84 24 40 01 00 00 4c 89 ef 41 89 45 24 5b 56 ff ff 48 ba 00 00 00 00 00 fc ff df 48 8d b8 c4 00 00 00 RSP: 0018:ffffc90000007a98 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffff110056f0ca5 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88802b786530 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000080000 R10: 000000000000000a R11: 0000000000000000 R12: 0000000000000002 R13: ffff88802b786530 R14: 0000000000000001 R15: ffff88802b785a00 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c38e428 CR3: 000000000db7c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5759 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 debug_object_activate+0x199/0x540 lib/debugobjects.c:709 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x25/0x3c0 kernel/time/hrtimer.c:1085 __run_hrtimer kernel/time/hrtimer.c:1706 [inline] __hrtimer_run_queues+0xaac/0xcc0 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5727 Code: c1 05 aa 11 9a 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90003fc7bd8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920007f8f7d RCX: 0000000000000001 RDX: 0000000000000001 RSI: ffffffff8b4cc7e0 RDI: ffffffff8bb084c0 RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffff934e6f8f R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffff888015881d48 R15: 0000000000000000 process_one_work+0x12a6/0x1b40 kernel/workqueue.c:3206 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10497 jiffies! g25725 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:27680 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.11.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline] RIP: 0010:smp_call_function_many_cond+0x4e7/0x1420 kernel/smp.c:856 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 4b 39 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 f7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90000107908 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9246940 RCX: ffffffff817e443b RDX: ffff888017a83c00 RSI: ffffffff817e4415 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1017248d29 R13: 0000000000000001 R14: ffff8880b9246948 R15: ffff8880b933ffc0 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000db7c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_flush arch/x86/kernel/alternative.c:2483 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:900 static_key_disable_cpuslocked+0x158/0x1c0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate mm/kfence/core.c:838 [inline] toggle_allocation_gate+0x143/0x250 mm/kfence/core.c:825 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf20 kernel/workqueue.c:3390 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244