rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=0e54/1/0x4000000000000000 softirq=109826/109826 fqs=3
rcu: 	(detected by 0, t=10503 jiffies, g=117621, q=721 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3 Comm: pool_workqueue_ 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:__sanitizer_cov_trace_const_cmp4+0xa/0x20 kernel/kcov.c:314
Code: 00 00 00 e9 58 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 89 f2 <89> fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0000:ffffc90000a08de0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff8880784e8300 RCX: ffffffff89c71d00
RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffff888027644800 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff89c71550 R14: ffff8880b8528640 R15: ffff8880b8528690
FS:  0000000000000000(0000) GS:ffff888123ee8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001230 CR3: 0000000079778000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 advance_sched+0x7b0/0xd20 net/sched/sch_taprio.c:935
 __run_hrtimer kernel/time/hrtimer.c:2032 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lockdep_unregister_key+0x12b/0x1d0 kernel/locking/lockdep.c:6616
Code: e8 da dd ff ff 48 83 2d 1a 29 9e 14 01 89 c3 e8 2b e0 ff ff 9c 58 f6 c4 02 0f 85 8a 00 00 00 f7 c5 00 02 00 00 74 01 fb 84 db <75> 40 5b 5d 41 5c e9 fa a8 09 00 9c 58 f6 c4 02 0f 84 16 ff ff ff
RSP: 0000:ffffc90000087d60 EFLAGS: 00000246
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8e29a0f5 RDI: ffffffff8c400f80
RBP: 0000000000000246 R08: 00000000000970b9 R09: ffffffff96962fd2
R10: 0000000000000200 R11: 0000000000000000 R12: ffffffff97ea4ec8
R13: ffff8880597ed000 R14: ffff8880597ed008 R15: ffff88802c11c801
 wq_unregister_lockdep kernel/workqueue.c:4949 [inline]
 pwq_release_workfn+0x618/0xb40 kernel/workqueue.c:5245
 kthread_worker_fn+0x300/0xbe0 kernel/kthread.c:1025
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread starved for 10490 jiffies! g117621 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27672 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7326
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 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: 0 UID: 0 PID: 0 Comm: swapper/0 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 86 8d 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 49 12 00 fb f4 <e9> bc 48 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e807e10 EFLAGS: 00000242
RAX: 0000000004450c8f RBX: ffffffff8e891480 RCX: ffffffff8bb952d5
RDX: 0000000000000000 RSI: ffffffff8e1a3c59 RDI: ffffffff8c400f80
RBP: fffffbfff1d12290 R08: 0000000000000001 R09: ffffed101708678d
R10: ffff8880b8433c6b R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff1d00fc6 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888123de8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f0e47d000 CR3: 00000000637b1000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:768
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x3a7/0x5b0 kernel/sched/idle.c:355
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
 rest_init+0x251/0x260 init/main.c:717
 start_kernel+0x48e/0x490 init/main.c:1175
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x158
 </TASK>