rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=9654/1/0x4000000000000000 softirq=124392/124392 fqs=0
rcu: (detected by 1, t=10506 jiffies, g=142377, q=39 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22711 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
RIP: 0010:debug_activate kernel/time/hrtimer.c:530 [inline]
RIP: 0010:enqueue_hrtimer+0xa9/0x2c0 kernel/time/hrtimer.c:1136
Code: c6 e8 9b 6c 13 00 45 85 e4 0f 84 6c 01 00 00 e8 8d 67 13 00 eb 05 e8 86 67 13 00 4c 89 f7 48 c7 c6 20 9c 0f 8c e8 87 ba 36 03 <41> 0f b6 d7 4c 89 f7 89 ee e8 19 02 00 00 49 89 dc 49 c1 ec 03 43
RSP: 0018:ffffc90000007d88 EFLAGS: 00000096
RAX: 0000000000000000 RBX: ffff8880b86284c0 RCX: ffffffff9a9ee501
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: 0000000000000000 R08: ffffffff9abf26d3 R09: 1ffffffff357e4da
R10: dffffc0000000000 R11: fffffbfff357e4db R12: 0000000000000001
R13: dffffc0000000000 R14: ffff88807966c300 R15: 0000000000000000
FS: 000055559371c500(0000) GS:ffff888124cc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faab934aff8 CR3: 00000000386ad000 CR4: 0000000000350ef0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:2090 [inline]
__hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2250
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:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947
Code: ff ff ff e8 30 ee 43 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 92 38 f2 11 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 5a d9 6c ff cc 48 8d 3d 47 38 da
RSP: 0018:ffffc90006736a80 EFLAGS: 00000292
RAX: eebd2d6aeacd3c00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000009ec81682 RSI: ffffffff8e69fd9a RDI: ffffffff8c6dad80
RBP: ffff888030955dc0 R08: ffffffff817811df R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff81b2c490 R12: ffffffff8ed5c8a0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:264 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6509 [inline]
kmem_cache_free+0x182/0x650 mm/slub.c:6636
netlink_broadcast_filtered+0xd9d/0xea0 net/netlink/af_netlink.c:1560
nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
nlmsg_multicast include/net/netlink.h:1184 [inline]
nlmsg_notify+0xe3/0x1a0 net/netlink/af_netlink.c:2618
inet6_ifmcaddr_notify+0x143/0x1e0 net/ipv6/mcast.c:943
__ipv6_dev_mc_dec+0x2f3/0x3a0 net/ipv6/mcast.c:1026
addrconf_leave_solict net/ipv6/addrconf.c:2273 [inline]
__ipv6_ifa_notify+0x77c/0xc60 net/ipv6/addrconf.c:6336
addrconf_ifdown+0xe7a/0x1a30 net/ipv6/addrconf.c:4013
addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1
notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2313 [inline]
call_netdevice_notifiers net/core/dev.c:2327 [inline]
netif_close_many+0x463/0x660 net/core/dev.c:1829
netif_close_many_and_unlock net/core/dev.c:12454 [inline]
unregister_netdevice_many_notify+0x843/0x2140 net/core/dev.c:12524
unregister_netdevice_many net/core/dev.c:12632 [inline]
unregister_netdevice_queue+0x2f5/0x340 net/core/dev.c:12433
unregister_netdevice include/linux/netdevice.h:3490 [inline]
nsim_destroy+0x275/0x800 drivers/net/netdevsim/netdev.c:1198
__nsim_dev_port_del+0x14e/0x200 drivers/net/netdevsim/dev.c:1472
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1486 [inline]
nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1710
nsim_drv_remove+0x58/0x170 drivers/net/netdevsim/dev.c:1725
device_remove drivers/base/dd.c:616 [inline]
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372
bus_remove_device+0x444/0x560 drivers/base/bus.c:664
device_del+0x524/0x8f0 drivers/base/core.c:3965
device_unregister+0x21/0xf0 drivers/base/core.c:4006
nsim_bus_dev_del drivers/net/netdevsim/bus.c:488 [inline]
del_device_store+0x2b5/0x370 drivers/net/netdevsim/bus.c:244
kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x612/0xba0 fs/read_write.c:687
ksys_write+0x150/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7e66d5e9ce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007fff9d087498 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000055559371c500 RCX: 00007f7e66d5e9ce
RDX: 0000000000000001 RSI: 00007fff9d087520 RDI: 0000000000000005
RBP: 00007f7e66e36163 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff9d087520 R14: 00007f7e67b54620 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 10506 jiffies! g142377 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27472 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 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: 12169 Comm: kworker/u8:19 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:csd_lock kernel/smp.c:396 [inline]
RIP: 0010:smp_call_function_many_cond+0x628/0x1500 kernel/smp.c:944
Code: 00 44 8b 3b 44 89 fe 83 e6 01 31 ff e8 01 59 0c 00 41 83 e7 01 75 07 e8 f6 53 0c 00 eb 3f f3 90 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 04 04 84 c0 75 0f f7 03 01 00 00 00 74 1d e8 d2 53 0c 00
RSP: 0018:ffffc90003997720 EFLAGS: 00000293
RAX: dffffc0000000000 RBX: ffff8880b8643708 RCX: ffff888022b49f40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003997870 R08: ffff888022b4b4df R09: 1ffff1100456969b
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170c86e1
R13: 0000000000000000 R14: ffff8880b8643700 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888124dc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2dcf20 CR3: 000000000eb48000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2641 [inline]
smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2851
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:909
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 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