rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=67c4/1/0x4000000000000000 softirq=34026/34027 fqs=1 rcu: (detected by 1, t=10506 jiffies, g=29205, q=304 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5834 Comm: syz-executor Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline] RIP: 0010:queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline] RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline] RIP: 0010:do_raw_spin_unlock+0x65/0x8b0 kernel/locking/spinlock_debug.c:141 Code: 34 04 00 00 81 3a ad 4e ad de 0f 85 05 01 00 00 4c 89 ff be 04 00 00 00 e8 b8 e5 8c 00 4c 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 <0f> 85 2a 04 00 00 41 83 3f 00 0f 84 9f 01 00 00 4d 8d 6f 10 4d 89 RSP: 0018:ffffc90000007c60 EFLAGS: 00000046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff8171c4f8 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b862c880 RBP: ffffc90000007d50 R08: ffff8880b862c883 R09: 1ffff110170c5910 R10: dffffc0000000000 R11: ffffed10170c5911 R12: dffffc0000000000 R13: 1ffff92000000f98 R14: ffffc90000007ce0 R15: ffff8880b862c880 FS: 000055556b77e500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055556b77e808 CR3: 00000000611c4000 CR4: 0000000000350ef0 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock_irqrestore+0x81/0x140 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x477/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829 Code: 2b 00 74 08 4c 89 f7 e8 8a 4e 8e 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003b778e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200076ef28 RCX: 55b5456a4de73e00 RDX: dffffc0000000000 RSI: ffffffff8c0adcc0 RDI: ffffffff8c610360 RBP: ffffc90003b77a28 R08: ffffffff942cc807 R09: 1ffffffff2859900 R10: dffffc0000000000 R11: fffffbfff2859901 R12: 1ffff9200076ef24 R13: dffffc0000000000 R14: ffffc90003b77940 R15: 0000000000000246 debug_objects_fill_pool+0xa0/0x9f0 lib/debugobjects.c:614 __debug_object_init+0xa4/0x400 lib/debugobjects.c:627 hrtimer_init_sleeper_on_stack kernel/time/hrtimer.c:448 [inline] hrtimer_nanosleep+0xb0/0x3f0 kernel/time/hrtimer.c:2078 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1411 [inline] __se_sys_clock_nanosleep+0x32d/0x3c0 kernel/time/posix-timers.c:1388 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc88b3b0805 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 c6 57 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 1f 58 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffe1c53d700 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000220 RCX: 00007fc88b3b0805 RDX: 00007ffe1c53d740 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe1c53d79c R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 0000000000035910 R14: 0000000000035906 R15: 00007ffe1c53d7f0 rcu: rcu_preempt kthread starved for 10500 jiffies! g29205 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:25136 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x18af/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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: 3435 Comm: kworker/u8:7 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1a04/0x2ca0 kernel/smp.c:884 Code: 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 41 ef 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 25 ef 0b 00 eb e4 44 89 e9 80 e1 07 80 c1 03 38 c1 7c e2 RSP: 0018:ffffc9000bda76e0 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 1ffff110170c8ca1 RCX: ffff8880317d3c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000bda78e0 R08: ffffffff8188fb1a R09: 1ffffffff2859900 R10: dffffc0000000000 R11: fffffbfff2859901 R12: dffffc0000000000 R13: ffff8880b8646508 R14: ffff8880b873fc80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f972cf60f40 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244