rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6956/1:b..l (detected by 0, t=10502 jiffies, g=66717, q=1007) task:kworker/u4:13 state:R running task stack:24216 pid: 6956 ppid: 2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 0c 75 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003cdf8e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200079bf28 RCX: 1ffff9200079bec8 RDX: dffffc0000000000 RSI: ffffffff8a8b3da0 RDI: ffffffff8ad904c0 RBP: ffffc90003cdfa40 R08: dffffc0000000000 R09: fffffbfff20e2419 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200079bf24 R13: dffffc0000000000 R14: ffffc90003cdf940 R15: 0000000000000246 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline] batadv_iv_ogm_schedule+0x429/0x1000 net/batman-adv/bat_iv_ogm.c:869 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10500 jiffies! g66717 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:26144 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9670 Comm: syz.2.1836 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:seqcount_lockdep_reader_access+0x11/0x220 include/linux/seqlock.h:98 Code: 41 5f 5d c3 e8 00 ad 10 00 0f 0b e9 35 fc ff ff e8 e4 9f c4 08 0f 1f 40 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 <48> 81 ec 80 00 00 00 65 48 8b 04 25 28 00 00 00 48 89 44 24 60 49 RSP: 0018:ffffc90000dcf8c0 EFLAGS: 00000086 RAX: 000000be67372f8a RBX: 0000000000000000 RCX: ffff8880231e3b80 RDX: 0000000000010100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000dcf8f0 R08: ffffffff816fafe5 R09: fffffbfff1bd2c16 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000002710 R13: 000000000002725c R14: 0000000000000001 R15: ffff888023e04900 FS: 00007f7a3eb876c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202a9000 CR3: 0000000083265000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get+0x7f/0x270 kernel/time/timekeeping.c:831 hrtimer_forward_now include/linux/hrtimer.h:508 [inline] perf_swevent_hrtimer+0x4aa/0x560 kernel/events/core.c:10887 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:168 [inline] RIP: 0010:unwind_next_frame+0x1f3/0x1fa0 arch/x86/kernel/unwind_orc.c:448 Code: 02 c5 02 0b 00 44 0f 45 f1 41 8d 46 ff 39 e8 0f 86 a7 15 00 00 89 e8 48 8d 1c 85 d0 30 f5 8e 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 3d 17 00 00 44 8b 23 89 e8 ff c0 48 8d 1c 85 d0 30 f5 RSP: 0018:ffffc90000dcfee8 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffffffff8f134eb8 RCX: 000000000009607f RDX: dffffc0000000000 RSI: ffffffff88877aa3 RDI: 0000000000000001 RBP: 000000000007877a R08: 0000000000000007 R09: ffffc90000dd0090 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001b9ffa R13: ffffffff88877aa2 R14: 000000000009607f R15: ffffc90000dcffa0 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xf1/0x270 mm/slub.c:4559 skb_free_head net/core/skbuff.c:655 [inline] skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb net/core/skbuff.c:756 [inline] consume_skb+0xa3/0x140 net/core/skbuff.c:914 netlink_broadcast_filtered+0x1083/0x11a0 net/netlink/af_netlink.c:1536 netlink_broadcast net/netlink/af_netlink.c:1558 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0xf7/0x1b0 net/netlink/af_netlink.c:2546 neigh_cleanup_and_release+0xa5/0x260 net/core/neighbour.c:101 neigh_del net/core/neighbour.c:197 [inline] neigh_remove_one+0x4b1/0x5c0 net/core/neighbour.c:218 neigh_forced_gc net/core/neighbour.c:251 [inline] neigh_alloc net/core/neighbour.c:429 [inline] ___neigh_create+0x45a/0x2220 net/core/neighbour.c:591 ip6_finish_output2+0x11c5/0x15a0 net/ipv6/ip6_output.c:127 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xae0/0x13c0 net/ipv6/ndisc.c:511 addrconf_rs_timer+0x357/0x610 net/ipv6/addrconf.c:3959 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:finish_lock_switch+0x91/0x100 kernel/sched/core.c:4782 Code: 45 31 c9 68 97 9b 59 81 e8 9c 11 09 00 48 83 c4 08 4c 89 ff e8 50 db fe ff 66 90 4c 89 ff e8 d6 48 e4 08 e8 51 3f 2d 00 fb 5b <41> 5c 41 5d 41 5e 41 5f c3 44 89 f1 80 e1 07 80 c1 03 38 c1 7c 87 RSP: 0018:ffffc900048eed38 EFLAGS: 00000286 RAX: 90ecd95060b81d00 RBX: ffff888076391df4 RCX: ffffffff81631ae8 RDX: dffffc0000000000 RSI: ffffffff8a8b2b00 RDI: ffffffff8ad904c0 RBP: ffffc900048eedb0 R08: dffffc0000000000 R09: fffffbfff20e242a R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff1101722760b R14: ffff8880b913b058 R15: ffff8880b913a300 finish_task_switch+0x134/0x630 kernel/sched/core.c:4899 context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12cc/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 unwind_next_frame+0x144d/0x1fa0 arch/x86/kernel/unwind_orc.c:616 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xf1/0x270 mm/slub.c:4559 tomoyo_realpath_from_path+0x5ad/0x5e0 security/tomoyo/realpath.c:291 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x273/0x6b0 security/tomoyo/file.c:822 security_path_truncate+0xcf/0x120 security/security.c:1214 handle_truncate fs/namei.c:3263 [inline] do_open fs/namei.c:3612 [inline] path_openat+0x2840/0x2f20 fs/namei.c:3742 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7a4072fef9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7a3eb87038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f7a408e8058 RCX: 00007f7a4072fef9 RDX: 000000000000275f RSI: 00000000200001c0 RDI: ffffffffffffff9c RBP: 00007f7a407a2b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7a408e8058 R15: 00007ffd427b24c8