IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=7094/1/0x4000000000000000 softirq=50615/50616 fqs=280 rcu: (detected by 1, t=10502 jiffies, g=62201, q=1482 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 15439 Comm: syz.3.2631 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4628 [inline] RIP: 0010:__lock_acquire+0xe8d/0x7c80 kernel/locking/lockdep.c:5121 Code: 24 40 8b 18 48 85 db 4c 8b b4 24 a8 00 00 00 74 5a 83 fb 31 0f 83 50 5d 00 00 48 8d 04 9b 49 8d 5c c6 f8 48 89 d8 48 c1 e8 03 <42> 0f b6 04 00 84 c0 0f 85 51 5d 00 00 8b 1b 48 8b 44 24 48 42 0f RSP: 0018:ffffc90000007900 EFLAGS: 00000802 RAX: 1ffff110047f652a RBX: ffff888023fb2950 RCX: ffffffff81671390 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da5508 RBP: ffffc90000007b48 R08: dffffc0000000000 R09: 1ffffffff21b4aa1 R10: dffffc0000000000 R11: fffffbfff21b4aa2 R12: 0000000000000000 R13: ffff888023fb1e00 R14: ffff888023fb28e0 R15: 94545a8047fe9384 FS: 00007fe4602726c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff594800218 CR3: 0000000061dd8000 CR4: 00000000003506f0 Call Trace: lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1759 [inline] __hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1819 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 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:444 [inline] RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x5e/0xb0 kernel/rcu/tree.c:700 Code: 03 42 80 3c 38 00 74 08 4c 89 f7 e8 7c 42 6d 00 48 c7 c3 68 6d 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 2f <8b> 03 65 ff 0d 41 21 94 7e 74 0c 83 e0 04 c1 e8 02 5b 41 5e 41 5f RSP: 0018:ffffc90005257460 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b8e36d68 RCX: 28d649b130016d00 RDX: 0000000000000000 RSI: ffffffff8afc70a0 RDI: ffffffff8afc7060 RBP: ffffc90005257590 R08: ffffffff8e4a922f R09: 1ffffffff1c95245 R10: dffffc0000000000 R11: fffffbfff1c95246 R12: 1ffff92000a4ae9c R13: ffffffff8cd2fc20 R14: ffffffff8c7d3a30 R15: dffffc0000000000 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xcb/0x410 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] page_ext_get+0x3e/0x2b0 mm/page_ext.c:508 page_table_check_clear+0x4a/0x6a0 mm/page_table_check.c:74 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] zap_pte_range mm/memory.c:1428 [inline] zap_pmd_range mm/memory.c:1570 [inline] zap_pud_range mm/memory.c:1599 [inline] zap_p4d_range mm/memory.c:1620 [inline] unmap_page_range+0x1ad1/0x2fe0 mm/memory.c:1641 unmap_vmas+0x25e/0x3a0 mm/memory.c:1731 unmap_region+0x1fb/0x340 mm/mmap.c:2344 do_vmi_align_munmap+0xffe/0x1660 mm/mmap.c:2592 do_vmi_munmap+0x252/0x2d0 mm/mmap.c:2660 __vm_munmap+0x193/0x3c0 mm/mmap.c:2961 __do_sys_munmap mm/mmap.c:2978 [inline] __se_sys_munmap mm/mmap.c:2975 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:2975 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe45f38ec37 Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 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:00007fe460271e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fe45f38ec37 RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007fe4551f7000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009687 R10: 000020000001c302 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fe460271ef0 R14: 00007fe460271eb0 R15: 00007fe4551f7000 rcu: rcu_preempt kthread starved for 9620 jiffies! g62201 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:27496 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148 Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d a3 16 3a 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56 RSP: 0018:ffffc90000187de0 EFLAGS: 000002c2 RAX: 05ea1f7863b0dd00 RBX: ffffffff8161925b RCX: 05ea1f7863b0dd00 RDX: 0000000000000001 RSI: ffffffff8aaabaa0 RDI: ffffffff8afc70c0 RBP: ffffc90000187f20 R08: ffff8880b8f36d6b R09: 1ffff110171e6dad R10: dffffc0000000000 R11: ffffed10171e6dae R12: ffffffff8e4a9228 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1100364e780 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000232a6000 CR4: 00000000003506e0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:753 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97 cpuidle_idle_call kernel/sched/idle.c:170 [inline] do_idle+0x1eb/0x510 kernel/sched/idle.c:282 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380 start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323 secondary_startup_64_no_verify+0x179/0x17b IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available IPVS: wrr: UDP 224.0.0.2:0 - no destination available