rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=6c6c/1/0x4000000000000000 softirq=116459/116460 fqs=4
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P26100/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=122593, q=143 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3 Comm: pool_workqueue_ Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__remove_hrtimer kernel/time/hrtimer.c:1115 [inline]
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1757 [inline]
RIP: 0010:__hrtimer_run_queues+0x380/0xc60 kernel/time/hrtimer.c:1841
Code: bc 24 90 00 00 00 4c 89 e6 e8 8c 53 94 09 84 c0 74 07 e8 d3 5e 12 00 eb 69 48 8b 54 24 38 48 89 d0 48 c1 e8 03 42 0f b6 04 28 <84> c0 0f 85 41 05 00 00 44 8b 2a bf 20 00 00 00 44 89 ee e8 e8 62
RSP: 0018:ffffc90000007d40 EFLAGS: 00000016
RAX: 0000000000000000 RBX: ffff8880b8827d08 RCX: dffffc0000000000
RDX: ffff8880b8827cc8 RSI: ffff8880b8827d10 RDI: ffff888020ed1348
RBP: ffffc90000007e90 R08: ffffffff8f7cd477 R09: 1ffffffff1ef9a8e
R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: ffff888020ed1340
R13: dffffc0000000000 R14: ffff8880b8827ac0 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000140 CR3: 0000000082c27000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_unregister_key+0x2c5/0x310 kernel/locking/lockdep.c:6616
Code: 65 48 8b 05 8d a8 d0 10 48 3b 44 24 10 0f 84 26 fe ff ff e8 3d 99 a8 09 e8 68 9a a8 09 41 f7 c7 00 02 00 00 74 bd fb 40 84 ed <75> bc eb cd 90 0f 0b 90 e9 19 ff ff ff 90 0f 0b 90 e9 2a ff ff ff
RSP: 0018:ffffc90000087be0 EFLAGS: 00000246
RAX: 7feef70c9983bd00 RBX: ffff888055ba6538 RCX: 7feef70c9983bd00
RDX: ffffffff9331d358 RSI: ffffffff8d720264 RDI: ffffffff8bbf05e0
RBP: ffff888055ba6500 R08: 0000000000000000 R09: ffffffff81aa73f8
R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: 0000000000000000
R13: 0000000000001000 R14: 0000000000000001 R15: 0000000000000217
 wq_unregister_lockdep kernel/workqueue.c:4848 [inline]
 pwq_release_workfn+0x6d5/0x870 kernel/workqueue.c:5144
 kthread_worker_fn+0x507/0xb60 kernel/kthread.c:1010
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:syz-executor    state:R  running task     stack:22568 pid:26100 tgid:26100 ppid:26082  task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5893
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 4b ba d0 10 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000520e6d8 EFLAGS: 00000206
RAX: c4b4d7a8360ded00 RBX: 0000000000000206 RCX: c4b4d7a8360ded00
RDX: 0000000000000001 RSI: ffffffff8d8f29ba RDI: ffffffff8bbf05e0
RBP: ffff88802393e618 R08: 0000000000000000 R09: ffffffff81aaa4fd
R10: dffffc0000000000 R11: ffffffff81ac2d30 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8df3d2e0 R15: ffff88802393dac0
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 is_module_text_address+0x18b/0x1e0 kernel/module/main.c:3847
 kernel_text_address+0x94/0xe0 kernel/extable.c:119
 __kernel_text_address+0xd/0x40 kernel/extable.c:79
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5642 [inline]
 __kmalloc_noprof+0x411/0x7f0 mm/slub.c:5654
 kmalloc_noprof include/linux/slab.h:961 [inline]
 switchdev_deferred_enqueue+0x2d/0x240 net/switchdev/switchdev.c:117
 br_mc_disabled_update net/bridge/br_multicast.c:1994 [inline]
 br_multicast_add_port+0x257/0x410 net/bridge/br_multicast.c:2040
 new_nbp+0x313/0x440 net/bridge/br_if.c:445
 br_add_if+0x28e/0xec0 net/bridge/br_if.c:599
 do_set_master+0x533/0x6d0 net/core/rtnetlink.c:2956
 do_setlink+0xcf0/0x41c0 net/core/rtnetlink.c:3158
 rtnl_changelink net/core/rtnetlink.c:3769 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3928 [inline]
 rtnl_newlink+0x1619/0x1c80 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6951
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f325fd90e5c
RSP: 002b:00007ffde68f7640 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3260b14620 RCX: 00007f325fd90e5c
RDX: 0000000000000028 RSI: 00007f3260b14670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffde68f7694 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f3260b14670 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10494 jiffies! g122593 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:27288 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 16724 Comm: kworker/u8:39 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd38/0x12d0 kernel/smp.c:877
Code: 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 6f 0b 00 eb 38 f3 90 42 0f b6 04 2b <84> c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 45 6f 0b 00 eb e4 44
RSP: 0018:ffffc90003eaf640 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11017108441 RCX: ffff88802922bc80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003eaf7c0 R08: ffffffff8f7cd477 R09: 1ffffffff1ef9a8e
R10: dffffc0000000000 R11: fffffbfff1ef9a8f R12: ffff8880b8842208
R13: dffffc0000000000 R14: ffff8880b893b240 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812623e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6f0958ffe0 CR3: 000000000dd38000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 on_each_cpu include/linux/smp.h:71 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2713 [inline]
 smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>