rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...0: (1 ticks this GP) idle=ceec/1/0x4000000000000000 softirq=10108/10108 fqs=36 rcu: hardirqs softirqs csw/system rcu: number: 0 0 0 rcu: cputime: 0 0 0 ==> 51860(ms) rcu: (detected by 0, t=10502 jiffies, g=13101, q=1419 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2915 Comm: kworker/1:2 Not tainted 6.8.0-rc2-syzkaller-g41bccc98fb79 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: events_power_efficient gc_worker RIP: 0010:check_region_inline mm/kasan/generic.c:169 [inline] RIP: 0010:kasan_check_range+0xe0/0x190 mm/kasan/generic.c:189 Code: 83 c0 01 48 39 c2 0f 84 89 00 00 00 80 38 00 74 ee 48 89 c2 b8 01 00 00 00 48 85 d2 74 1e 41 83 e2 07 49 39 d1 75 0a 45 3a 11 01 00 00 00 7c 0b 44 89 c2 e8 21 ed ff ff 83 f0 01 5b 5d 41 5c RSP: 0018:ffffc900001f0d88 EFLAGS: 00000097 RAX: 0000000000000001 RBX: fffff5200003e1bb RCX: ffffffff8167d2ae RDX: fffff5200003e1ba RSI: 0000000000000004 RDI: ffffc900001f0dd0 RBP: fffff5200003e1ba R08: 0000000000000001 R09: fffff5200003e1ba R10: 0000000000000003 R11: 0000000000000003 R12: ffff8880b992bac8 R13: ffff8880b992bad0 R14: ffff88806a53a340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3e2bc2e440 CR3: 000000007f7b7000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1295 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x12e/0x2b0 kernel/locking/spinlock_debug.c:116 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x2bd/0xc20 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline] RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:345 [inline] RIP: 0010:gc_worker+0x2e1/0x17e0 net/netfilter/nf_conntrack_core.c:1490 Code: 00 00 48 c7 c7 c8 de 3a 8f e8 3b 5d a9 f8 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 59 0a c9 f8 48 85 db 58 0f 85 9f 10 00 00 ba 0e c9 f8 eb 07 e8 b3 0e c9 f8 f3 90 44 8b 35 1a de 7c 06 31 RSP: 0018:ffffc9000b077bf0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff88be0c5d RDX: ffff88802a251dc0 RSI: ffffffff88be0c6c RDI: 0000000000000007 RBP: ffff888028c00000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: 00000000000028d5 R13: dffffc0000000000 R14: 00000000000051a9 R15: 0000000000040000 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787 kthread+0x2c6/0x3a0 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:242 rcu: rcu_preempt kthread starved for 3500 jiffies! g13101 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:28080 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0xf12/0x5c00 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6817 schedule_timeout+0x137/0x290 kernel/time/timer.c:2183 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1663 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1862 kthread+0x2c6/0x3a0 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:242 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 49 Comm: kworker/u4:3 Not tainted 6.8.0-rc2-syzkaller-g41bccc98fb79 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:check_kcov_mode kernel/kcov.c:175 [inline] RIP: 0010:write_comp_data+0x2f/0x80 kernel/kcov.c:236 Code: f8 49 89 f1 65 48 8b 14 25 40 c2 03 00 65 8b 05 af b8 7c 7e a9 00 01 ff 00 74 0f f6 c4 01 74 59 8b 82 fc 15 00 00 85 c0 74 4f <8b> 82 d8 15 00 00 83 f8 03 75 44 48 8b 82 e0 15 00 00 8b 92 dc 15 RSP: 0018:ffffc90000ba7928 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff8880b9941fe0 RCX: ffffffff817b4a48 RDX: ffff888013fd5940 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed10173283fd R13: 0000000000000001 R14: ffff8880b9941fe8 R15: ffff8880b983de40 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe5212d218 CR3: 000000000cf78000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: csd_lock_wait kernel/smp.c:311 [inline] smp_call_function_many_cond+0x508/0x1550 kernel/smp.c:855 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:2087 [inline] text_poke_bp_batch+0x655/0x750 arch/x86/kernel/alternative.c:2297 text_poke_flush arch/x86/kernel/alternative.c:2488 [inline] text_poke_flush arch/x86/kernel/alternative.c:2485 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2495 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:826 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:818 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787 kthread+0x2c6/0x3a0 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:242