rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9/2:b..l P5138/1:b..l P5761/1:b..l P5758/1:b..l rcu: (detected by 1, t=10502 jiffies, g=8593, q=614 ncpus=2) task:udevd state:R running task stack:27304 pid:5758 ppid:5138 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90004457620 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 9c7e4ade18c39c00 RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c8fa0 RBP: ffffc90004457730 R08: dffffc0000000000 R09: 1ffffffff2238ca0 R10: dffffc0000000000 R11: fffffbfff2238ca1 R12: 1ffff9200088aed0 R13: ffffffff8d1320e0 R14: 0000000000000246 R15: dffffc0000000000 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 __reset_page_owner+0x2e/0x190 mm/page_owner.c:145 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504 release_pages+0x1f7a/0x2200 mm/swap.c:1022 tlb_batch_pages_flush mm/mmu_gather.c:99 [inline] tlb_flush_mmu_free mm/mmu_gather.c:294 [inline] tlb_flush_mmu+0x379/0x510 mm/mmu_gather.c:301 tlb_finish_mmu+0xf9/0x220 mm/mmu_gather.c:425 exit_mmap+0x428/0xb90 mm/mmap.c:3315 __mmput+0x118/0x3c0 kernel/fork.c:1356 exit_mm+0x1f2/0x2c0 kernel/exit.c:569 do_exit+0x8dd/0x2460 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2ffeaf16c5 RSP: 002b:00007ffe63f63918 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000564b342d3f80 RCX: 00007f2ffeaf16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000564b3420b910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe63f63960 R14: 0000000000000000 R15: 0000000000000000 task:udevd state:R running task stack:27304 pid:5761 ppid:5138 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1523 [inline] zap_pmd_range mm/memory.c:1571 [inline] zap_pud_range mm/memory.c:1600 [inline] zap_p4d_range mm/memory.c:1621 [inline] unmap_page_range+0x2315/0x3000 mm/memory.c:1642 unmap_vmas+0x286/0x3f0 mm/memory.c:1732 exit_mmap+0x238/0xb90 mm/mmap.c:3302 __mmput+0x118/0x3c0 kernel/fork.c:1356 exit_mm+0x1f2/0x2c0 kernel/exit.c:569 do_exit+0x8dd/0x2460 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2ffeaf16c5 RSP: 002b:00007ffe63f63918 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000564b342385a0 RCX: 00007f2ffeaf16c5 RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000 RBP: 0000564b3420b910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe63f63960 R14: 0000000000000000 R15: 0000000000000000 task:udevd state:R running task stack:25160 pid:5138 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 unwind_next_frame+0x200f/0x2970 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 save_stack+0x125/0x230 mm/page_owner.c:128 __reset_page_owner+0x4e/0x190 mm/page_owner.c:149 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 __slab_free+0x35a/0x400 mm/slub.c:3736 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 getname_flags+0xbb/0x500 fs/namei.c:140 vfs_fstatat+0x111/0x1b0 fs/stat.c:298 __do_sys_newfstatat fs/stat.c:463 [inline] __se_sys_newfstatat fs/stat.c:457 [inline] __x64_sys_newfstatat+0x149/0x1f0 fs/stat.c:457 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f2ffeb11b0a RSP: 002b:00007ffe63f639f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000564b03448408 RCX: 00007f2ffeb11b0a RDX: 00007ffe63f63a00 RSI: 0000564b03436ef3 RDI: 00000000ffffff9c RBP: 0000564b3421e148 R08: 00063489548db180 R09: 0000000000745b4e R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe63f63a00 R14: 0000000000000000 R15: 00063489548db180 task:kworker/0:1 state:R running task stack:24424 pid:9 ppid:2 flags:0x00004000 Workqueue: mld mld_dad_work Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __local_bh_enable_ip+0x14b/0x1c0 kernel/softirq.c:413 ipv6_get_lladdr+0x2aa/0x3e0 net/ipv6/addrconf.c:1910 mld_newpack+0x430/0xbe0 net/ipv6/mcast.c:1757 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1854 add_grec+0x13ad/0x1660 net/ipv6/mcast.c:1992 mld_send_initial_cr+0xed/0x240 net/ipv6/mcast.c:2237 mld_dad_work+0x40/0x270 net/ipv6/mcast.c:2263 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 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: rcu_preempt kthread starved for 8405 jiffies! g8593 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:26568 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5832 Comm: syz.2.3 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:196 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 7b f8 23 03 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90000007300 EFLAGS: 00000046 RAX: 00000000000001e6 RBX: ffff8880b8e28280 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 00000000000001e6 RDI: 0000000000000838 RBP: 0000000000000000 R08: ffffffff8e8b19af R09: 1ffffffff1d16335 R10: dffffc0000000000 R11: fffffbfff1d16336 R12: dffffc0000000000 R13: 0000000010003ab8 R14: 00000000000001e6 R15: 0000000000000020 FS: 00007f89b2ca96c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c33f60f CR3: 000000005df8a000 CR4: 00000000003506f0 Call Trace: apic_write arch/x86/include/asm/apic.h:404 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:448 clockevents_program_event+0x1c0/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x5a1/0x9c0 kernel/time/hrtimer.c:1889 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+0x51/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:jhash2 include/linux/jhash.h:129 [inline] RIP: 0010:hash_stack lib/stackdepot.c:322 [inline] RIP: 0010:__stack_depot_save+0x6c/0x630 lib/stackdepot.c:382 Code: 7b 71 f5 75 83 fe 04 0f 82 83 00 00 00 44 89 e0 44 89 e1 48 89 da 03 0a 03 42 04 44 03 62 08 44 89 e7 c1 c7 04 44 29 e1 31 cf <41> 01 c4 29 f8 41 89 f8 41 c1 c0 06 41 31 c0 44 01 e7 45 89 c1 41 RSP: 0018:ffffc90000007568 EFLAGS: 00000206 RAX: 000000001448d559 RBX: ffffc900000075c0 RCX: 00000000491d4cc5 RDX: ffffc900000075e4 RSI: 0000000000000017 RDI: 000000007ea3b7c0 RBP: 0000000000000000 R08: 00000000f452ec71 R09: 00000000b429d58f R10: dffffc0000000000 R11: fffffbfff1d16336 R12: 00000000537befb0 R13: ffffc900000078a0 R14: 0000000000000010 R15: 0000000000000001 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_set_track+0x5f/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x270 mm/slub.c:3852 kfree_skb include/linux/skbuff.h:1264 [inline] ip6_mc_input+0xaa0/0xcb0 net/ipv6/ip6_input.c:589 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304 __netif_receive_skb_one_core net/core/dev.c:5646 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5760 process_backlog+0x391/0x6f0 net/core/dev.c:6088 __napi_poll+0xc0/0x460 net/core/dev.c:6650 napi_poll net/core/dev.c:6717 [inline] net_rx_action+0x616/0xc40 net/core/dev.c:6853 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__read_once_word_nocheck+0xc/0x10 include/asm-generic/rwonce.h:67 Code: 89 e1 80 e1 07 38 c1 0f 8c 5d fc ff ff 4c 89 e7 e8 69 eb a3 00 e9 50 fc ff ff 0f 1f 40 00 53 48 89 fb e8 e7 b3 4b 00 48 8b 03 <5b> c3 cc cc f3 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 RSP: 0018:ffffc9000498f8c8 EFLAGS: 00000246 RAX: ffffffff81967741 RBX: ffffc9000498fd40 RCX: 0000000000080000 RDX: ffffc9000e3de000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000498f9f8 R08: ffff88802a110000 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000002 R12: ffffc9000498f9a8 R13: dffffc0000000000 R14: ffffc9000498fd40 R15: ffffffff8f8e6a1c deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline] unwind_next_frame+0x15f9/0x2970 arch/x86/kernel/unwind_orc.c:585 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 ref_tracker_free+0x11f/0x840 lib/ref_tracker.c:239 __netns_tracker_free include/net/net_namespace.h:367 [inline] __sk_destruct+0x567/0x660 net/core/sock.c:2227 bpf_prog_test_run_skb+0xd6b/0x12b0 net/bpf/test_run.c:1087 bpf_prog_test_run+0x321/0x390 kernel/bpf/syscall.c:4132 __sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f89b1d9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f89b2ca9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f89b2016090 RCX: 00007f89b1d9ce59 RDX: 0000000000000050 RSI: 0000200000000080 RDI: 000000000000000a RBP: 00007f89b1e32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f89b2016128 R14: 00007f89b2016090 R15: 00007ffefc7efb38 net_ratelimit: 1953 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) net_ratelimit: 9378 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)