rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=0bdc/1/0x4000000000000000 softirq=26575/26575 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9144/1:b..l rcu: (detected by 0, t=10502 jiffies, g=22761, q=142 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 26 Comm: kworker/1:0 Not tainted 6.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1767 [inline] RIP: 0010:__hrtimer_run_queues+0x423/0xae0 kernel/time/hrtimer.c:1865 Code: ea 03 80 3c 02 00 0f 85 ac 05 00 00 49 8b 6c 24 20 48 89 de 48 89 ef e8 1b ca 12 00 48 39 dd 0f 8f ea 04 00 00 e8 9d cf 12 00 <48> c7 c0 34 96 62 90 48 ba 00 00 00 00 00 fc ff df 48 89 c1 83 e0 RSP: 0018:ffffc90000a28e30 EFLAGS: 00000046 RAX: 0000000080010001 RBX: 1bc16d674ec858c5 RCX: ffffffff81a72135 RDX: ffff88801d6a4880 RSI: ffffffff81a72143 RDI: 0000000000000006 RBP: 1836a38410000000 R08: 0000000000000006 R09: 1836a38410000000 R10: 1bc16d674ec858c5 R11: 0000000000000004 R12: ffff888056ee3340 R13: ffff8880b872c780 R14: ffff8880b872c680 R15: ffffffff896ad410 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555590f1f808 CR3: 000000005d522000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/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.part.0+0x155/0x380 kernel/locking/lockdep.c:5816 Code: b8 ff ff ff ff 65 0f c1 05 10 ca 6b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc90000a0fa70 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92000141f4f RCX: 00000000e0afe4dd RDX: 0000000000000001 RSI: ffffffff8b6cfde0 RDI: ffffffff8bd36860 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dd8b98 R10: ffffffff96ec5cc7 R11: 0000000000000002 R12: 0000000000000000 R13: ffffffff8e1bd0c0 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] gc_worker+0x242/0x16a0 net/netfilter/nf_conntrack_core.c:1532 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz.3.883 state:R running task stack:25664 pid:9144 tgid:9139 ppid:5833 task_flags:0x400040 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] finish_fault+0xbd0/0x10e0 mm/memory.c:5280 do_read_fault mm/memory.c:5414 [inline] do_fault mm/memory.c:5544 [inline] do_pte_missing+0xef8/0x3e10 mm/memory.c:4060 handle_pte_fault mm/memory.c:5907 [inline] __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6050 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6219 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x773/0x36f0 mm/gup.c:1491 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1929 __mm_populate+0x1d6/0x380 mm/gup.c:2032 mm_populate include/linux/mm.h:3386 [inline] vm_mmap_pgoff+0x2d3/0x3a0 mm/util.c:580 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:607 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0cef38d169 RSP: 002b:00007f0cf024b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f0cef5a6080 RCX: 00007f0cef38d169 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000400000000000 RBP: 00007f0cef40e2a0 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0cef5a6080 R15: 00007ffd40a01528 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g22761 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=17868 rcu: rcu_preempt kthread starved for 10502 jiffies! g22761 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27456 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244