rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 ticks this GP) idle=16b4/1/0x4000000000000000 softirq=77434/77434 fqs=11
rcu: (detected by 1, t=10502 jiffies, g=65269, q=1674 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6389 Comm: kworker/u8:13 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: netns cleanup_net
RIP: 0010:advance_sched+0xb25/0xc80 net/sched/sch_taprio.c:996
Code: 60 98 05 8d e8 8c 1f c5 f7 48 c7 c7 60 9c b5 8e 48 89 de e8 0d 06 c5 f7 e8 d8 b4 ce f7 b8 01 00 00 00 48 81 c4 90 00 00 00 5b <41> 5c 41 5d 41 5e 41 5f 5d e9 58 f2 32 f7 cc e8 c7 22 e9 f7 e9 c5
RSP: 0018:ffffc90000007da8 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 1ffff1100f4ca171 RCX: 0000000000010001
RDX: 0000000000000006 RSI: ffffffff8e4b12ee RDI: ffff88807a650000
RBP: 0000000000000001 R08: ffff88807d17c19f R09: 1ffff1100fa2f833
R10: dffffc0000000000 R11: ffffed100fa2f834 R12: ffff888054421000
R13: ffff88807d17c000 R14: dffffc0000000000 R15: ffff88807d17c340
FS: 0000000000000000(0000) GS:ffff888124f52000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558ef98a38 CR3: 0000000025a53000 CR4: 0000000000350ef0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:finish_task_switch+0x417/0xc60 kernel/sched/core.c:5361
Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 63 ca 3d 0a e8 8e a9 39 00 fb 4c 8b 65 c8 <49> 8d bc 24 f8 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0
RSP: 0018:ffffc9000382f120 EFLAGS: 00000202
RAX: 00000000001a8ccb RBX: ffff8880b863bf20 RCX: 0000000080000001
RDX: 0000000000000006 RSI: ffffffff8e22bab2 RDI: ffffffff8c4bdb80
RBP: ffffc9000382f170 R08: ffffffff90578af7 R09: 1ffffffff20af15e
R10: dffffc0000000000 R11: fffffbfff20af15f R12: ffff88807a650000
R13: ffff8880b863bee8 R14: dffffc0000000000 R15: 1ffff110170c77e4
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x17e1/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
rwsem_down_write_slowpath+0x87d/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1bc/0x200 kernel/locking/rwsem.c:1632
kernfs_remove_by_name_ns+0x4e/0x140 fs/kernfs/dir.c:1792
kernfs_remove_by_name include/linux/kernfs.h:644 [inline]
remove_files fs/sysfs/group.c:28 [inline]
sysfs_remove_group+0x101/0x2e0 fs/sysfs/group.c:328
sysfs_remove_groups+0x54/0xb0 fs/sysfs/group.c:352
netdev_queue_update_kobjects+0x5c1/0x6b0 net/core/net-sysfs.c:2051
remove_queue_kobjects net/core/net-sysfs.c:2149 [inline]
netdev_unregister_kobject+0x10b/0x450 net/core/net-sysfs.c:2304
unregister_netdevice_many_notify+0x1be4/0x2150 net/core/dev.c:12479
ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]
ops_undo_list+0x391/0x8d0 net/core/net_namespace.c:248
cleanup_net+0x572/0x810 net/core/net_namespace.c:702
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10480 jiffies! g65269 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:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 10202 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b5/0x14b0 kernel/smp.c:892
Code: 1e 89 de 83 e6 01 31 ff e8 d8 22 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 84 1e 0c 00 eb 37 f3 90 41 0f b6 04 1c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 69 1e 0c 00 eb e5 44 89
RSP: 0018:ffffc9000431f580 EFLAGS: 00000293
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88802ee83e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000431f6a8 R08: ffffffff90578af7 R09: 1ffffffff20af15e
R10: dffffc0000000000 R11: fffffbfff20af15f R12: 1ffff110170c85fd
R13: ffff8880b873c448 R14: ffff8880b8642fe8 R15: 0000000000000000
FS: 00005555696bf500(0000) GS:ffff888125052000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f67309eb580 CR3: 0000000074bc9000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c4/0x1090 arch/x86/mm/tlb.c:1451
dup_mmap+0x1786/0x1d90 mm/mmap.c:1905
dup_mm kernel/fork.c:1543 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1595
copy_process+0x1e3e/0x4390 kernel/fork.c:2289
kernel_clone+0x2d7/0x940 kernel/fork.c:2748
__do_sys_clone kernel/fork.c:2889 [inline]
__se_sys_clone kernel/fork.c:2873 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2873
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f03f57c6912
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffc150f50e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffc150f50e0 RCX: 00007f03f57c6912
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffc150f526c R08: 0000000000000000 R09: 0000000000000001
R10: 00005555696bf7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000006a9a4 R15: 00007ffc150f52c0