rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (2 ticks this GP) idle=be84/1/0x4000000000000000 softirq=52558/52559 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6115/1:b..l P5997/1:b..l rcu: (detected by 1, t=10502 jiffies, g=40529, q=86 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10337 Comm: syz.2.1069 Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38 Code: 44 88 1f e9 0e 14 a1 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 e9 e2 13 a1 f5 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000007ce8 EFLAGS: 00000002 RAX: ffffffff8b6b1700 RBX: 1ffff110170c4f82 RCX: 0000000000000010 RDX: 0000000000000018 RSI: 0000000000000000 RDI: ffff88801faed348 RBP: 0000000000000000 R08: ffff88801faed357 R09: ffff88801faed340 R10: dffffc0000000000 R11: ffffed1003f5da6b R12: ffff88801faed340 R13: dffffc0000000000 R14: ffff8880b8627c10 R15: ffff88801faed340 FS: 00007f91300646c0(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f44707a4fe8 CR3: 0000000064755000 CR4: 0000000000350ef0 Call Trace: rb_link_node include/linux/rbtree.h:63 [inline] rb_add_cached include/linux/rbtree.h:182 [inline] timerqueue_add+0x186/0x200 lib/timerqueue.c:40 __run_hrtimer kernel/time/hrtimer.c:1778 [inline] __hrtimer_run_queues+0x656/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 3b 1d 56 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 03 3e 1f f6 65 8b 05 ac ba 2e 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90004d7fb60 EFLAGS: 00000206 RAX: bb2516f06b45f400 RBX: 0000000000000216 RCX: bb2516f06b45f400 RDX: 0000000000000007 RSI: ffffffff8d998685 RDI: 0000000000000001 RBP: ffffc90004d7fbf0 R08: ffffffff8fa1eff7 R09: 1ffffffff1f43dfe R10: dffffc0000000000 R11: fffffbfff1f43dff R12: dffffc0000000000 R13: ffff8880b8627ac0 R14: ffff8880b8627ac0 R15: 1ffff920009aff6c clock_was_set+0x63b/0x7c0 kernel/time/hrtimer.c:972 do_settimeofday64+0x2ec/0x5e0 kernel/time/timekeeping.c:1407 __do_sys_clock_settime kernel/time/posix-timers.c:1132 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1116 [inline] __x64_sys_clock_settime+0x22c/0x280 kernel/time/posix-timers.c:1116 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f912f18e929 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:00007f9130064038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007f912f3b5fa0 RCX: 00007f912f18e929 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000 RBP: 00007f912f210b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f912f3b5fa0 R15: 00007ffeeec4ecf8 task:kworker/u8:9 state:R running task stack:22912 pid:5997 tgid:5997 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7113 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 9b 20 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90003007980 EFLAGS: 00000206 RAX: 1e67e6eb2aea4800 RBX: 0000000000000000 RCX: 1e67e6eb2aea4800 RDX: 0000000000000000 RSI: ffffffff8db86104 RDI: ffffffff8be29dc0 RBP: ffffffff8b3cd5d2 R08: 0000000000000000 R09: ffffffff8b3cd5d2 R10: dffffc0000000000 R11: ffffffff8b3cd500 R12: 0000000000000002 R13: ffffffff8e13f160 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:kworker/u8:14 state:R running task stack:21160 pid:6115 tgid:6115 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7113 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:memset+0xf/0x20 arch/x86/lib/memset_64.S:38 Code: 44 88 1f e9 0e 14 a1 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 e9 e2 13 a1 f5 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900044eec90 EFLAGS: 00000202 RAX: 1ffff9200089dd00 RBX: ffffc900044eeda0 RCX: 0000000000000001 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900044eedc7 RBP: dffffc0000000000 R08: ffffc900044eedc7 R09: ffffc900044eedb8 R10: dffffc0000000000 R11: fffff5200089ddb9 R12: ffffc900044ef160 R13: ffffc900044eedb8 R14: ffffc900044eed68 R15: ffffc900044eedb0 unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7280 [inline] addrconf_sysctl_unregister net/ipv6/addrconf.c:7306 [inline] addrconf_ifdown+0x152d/0x1880 net/ipv6/addrconf.c:4010 addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] unregister_netdevice_many_notify+0x15d8/0x2320 net/core/dev.c:12077 unregister_netdevice_many net/core/dev.c:12140 [inline] unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:11984 unregister_netdevice include/linux/netdevice.h:3379 [inline] _cfg80211_unregister_wdev+0x165/0x590 net/wireless/core.c:1256 ieee80211_remove_interfaces+0x49a/0x6d0 net/mac80211/iface.c:2362 ieee80211_unregister_hw+0x5d/0x2c0 net/mac80211/main.c:1683 mac80211_hwsim_del_radio+0x275/0x460 drivers/net/wireless/virtual/mac80211_hwsim.c:5671 hwsim_exit_net+0x584/0x640 drivers/net/wireless/virtual/mac80211_hwsim.c:6551 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:253 cleanup_net+0x4c5/0x800 net/core/net_namespace.c:686 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 10502 jiffies! g40529 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 10340 Comm: syz.7.1068 Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xf6e/0x12d0 kernel/smp.c:885 Code: 89 ee 83 e6 01 31 ff e8 d0 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 7b 74 0b 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 07 01 00 00 00 74 1e e8 60 74 0b 00 eb e5 44 89 RSP: 0018:ffffc9000c0575e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b873b1c0 RCX: 0000000000080000 RDX: ffffc9000c0c9000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000c057740 R08: ffffffff8fa1eff7 R09: 1ffffffff1f43dfe R10: dffffc0000000000 R11: fffffbfff1f43dff R12: 1ffff110170c8385 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641c28 FS: 00007f44714df6c0(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004ac0 CR3: 000000007b0a3000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline] smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2901 __static_call_transform+0x4eb/0x750 arch/x86/kernel/static_call.c:111 arch_static_call_transform+0x98/0xc0 arch/x86/kernel/static_call.c:-1 __static_call_update+0xe4/0x5d0 kernel/static_call_inline.c:147 tracepoint_update_call kernel/tracepoint.c:271 [inline] tracepoint_add_func+0x6f7/0xa10 kernel/tracepoint.c:319 tracepoint_probe_register_prio_may_exist+0x5f/0xa0 kernel/tracepoint.c:435 bpf_raw_tp_link_attach+0x4ff/0x6b0 kernel/bpf/syscall.c:4007 bpf_raw_tracepoint_open+0x19b/0x1f0 kernel/bpf/syscall.c:4038 __sys_bpf+0x3cd/0x860 kernel/bpf/syscall.c:5878 __do_sys_bpf kernel/bpf/syscall.c:5943 [inline] __se_sys_bpf kernel/bpf/syscall.c:5941 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5941 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f447058e929 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:00007f44714df038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f44707b5fa0 RCX: 00007f447058e929 RDX: 0000000000000010 RSI: 0000200000000080 RDI: 0000000000000011 RBP: 00007f4470610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f44707b5fa0 R15: 00007ffd870b6718