rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (3 ticks this GP) idle=023/1/0x4000000000000000 softirq=10498/10498 fqs=396 (detected by 0, t=10506 jiffies, g=11981, q=680) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 21 Comm: kworker/1:0 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:debug_deactivate+0x90/0x1c0 kernel/time/hrtimer.c:473 Code: 0f 92 c3 40 0f 92 c6 bf 02 00 00 00 e8 89 e0 0f 00 84 db 74 10 e8 a0 c6 fb ff 84 c0 74 1c e8 17 de 0f 00 eb 05 e8 10 de 0f 00 <5b> 41 5e 41 5f 5d c3 e8 04 de 0f 00 0f 0b eb a4 e8 fb dd 0f 00 0f RSP: 0000:ffffc90000dd0cf8 EFLAGS: 00000006 RAX: ffffffff8167e609 RBX: 0000000000000001 RCX: ffff888016a91dc0 RDX: 0000000000010000 RSI: ffffffff8a599320 RDI: ffffffff8a5992e0 RBP: ffffc90000dd0e98 R08: dffffc0000000000 R09: fffffbfff1ad2dd6 R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: ffff8880b912a390 R13: 1ffff11017225472 R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f37b0700000 CR3: 000000001e866000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1658 [inline] __hrtimer_run_queues+0x2db/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106 Code: f9 4d 85 e4 75 16 e8 94 31 62 f9 eb 15 e8 8d 31 62 f9 e8 e8 9a 92 01 4d 85 e4 74 ea e8 7e 31 62 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00 RSP: 0000:ffffc90000db7a20 EFLAGS: 00000293 RAX: ffffffff881592a2 RBX: 0000000000000000 RCX: ffff888016a91dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000db7ad0 R08: dffffc0000000000 R09: fffffbfff1ff6e2c R10: fffffbfff1ff6e2c R11: 1ffffffff1ff6e2b R12: 0000000000000200 R13: ffff88813fea1218 R14: 1ffff920001b6f44 R15: dffffc0000000000 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline] gc_worker+0x2e2/0x13a0 net/netfilter/nf_conntrack_core.c:1472 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 8528 jiffies! g11981 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:27848 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 5530 Comm: syz-executor Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969 Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 a6 46 0b 00 83 e3 01 75 07 e8 3c 43 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7 RSP: 0018:ffffc9000122f8a0 EFLAGS: 00000293 RAX: ffffffff816c810b RBX: 0000000000000001 RCX: ffff88807d4d1dc0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000122f9e0 R08: dffffc0000000000 R09: fffffbfff1ff6e1f R10: fffffbfff1ff6e1f R11: 1ffffffff1ff6e1e R12: ffff8880b9140588 R13: 1ffff110172280b1 R14: ffff8880b903b380 R15: 0000000000000001 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135 __flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline] flush_tlb_multi arch/x86/mm/tlb.c:946 [inline] flush_tlb_mm_range+0x360/0x560 arch/x86/mm/tlb.c:1034 change_protection_range mm/mprotect.c:358 [inline] change_protection+0x17d9/0x18f0 mm/mprotect.c:375 mprotect_fixup+0x6d0/0x800 mm/mprotect.c:497 do_mprotect_pkey+0x657/0x910 mm/mprotect.c:636 __do_sys_mprotect mm/mprotect.c:662 [inline] __se_sys_mprotect mm/mprotect.c:659 [inline] __x64_sys_mprotect+0x7c/0x90 mm/mprotect.c:659 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f37b05f4fb7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc2d58ef68 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f37b0778700 RCX: 00007f37b05f4fb7 RDX: 0000000000000001 RSI: 0000000000089000 RDI: 00007f37b06e8000 RBP: 00007ffc2d58f0a8 R08: 000055558179a810 R09: 000055558179a830 R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffc2d58f0c0 R13: 00007ffc2d58f0a8 R14: 00007ffc2d58f040 R15: 00007ffc2d58f038