rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (2 GPs behind) idle=a094/0/0x1 softirq=23708/23709 fqs=147
rcu: 	(detected by 0, t=10502 jiffies, g=22157, q=542 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:advance_sched+0x3d8/0xc90 net/sched/sch_taprio.c:955
Code: ff ff e8 db 63 0f f8 e9 28 08 00 00 e8 d1 63 0f f8 4c 8b 3c 24 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 4c 89 e7 e8 9e 8c 79 f8 49 8b 87 10 01 00 00 48 89 44 24 28
RSP: 0018:ffffc90000a08c70 EFLAGS: 00000046
RAX: 1ffff110057c6622 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 000000304ce4d4a2
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: ffff88802be33110
R13: ffff88804d1eb000 R14: 000000304ce4d4a2 R15: ffff88802be33000
FS:  0000000000000000(0000) GS:ffff888125566000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8eeba4e9d3 CR3: 00000000640aa000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x53a/0xcc0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x42b/0x1010 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x460 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 8e 6d 02 c3 cc cc cc cc 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 0f 00 2d 43 4d 1c 00 fb f4 <e9> 7c ea 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 00000242
RAX: 00000000000aad37 RBX: ffffffff819a80dd RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8def1a36 RDI: ffffffff8c27a480
RBP: ffffc90000197f10 R08: ffff8880b873395b R09: 1ffff110170e672b
R10: dffffc0000000000 R11: ffffed10170e672c R12: ffffffff901172b0
R13: 1ffff11003b5c000 R14: 0000000000000001 R15: 0000000000000001
 arch_safe_halt arch/x86/kernel/process.c:766 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1bd/0x500 kernel/sched/idle.c:332
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>
rcu: rcu_preempt kthread starved for 10208 jiffies! g22157 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:27664 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7004
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:467
 ret_from_fork+0x51e/0xb90 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: 6794 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d 44 13 55 0c 48 89 de 5b e9 33 79 5e 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d 68 13 56 11 65 8b 15 89 13 56
RSP: 0018:ffffc9001b4b7558 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff110170e812d RCX: ffff88802f8edac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9001b4b76a0 R08: ffffffff901172b7 R09: 1ffffffff2022e56
R10: dffffc0000000000 R11: fffffbfff2022e57 R12: ffff8880b8740968
R13: dffffc0000000000 R14: ffff8880b863bf80 R15: 0000000000000001
FS:  00007fdfcaf41880(0000) GS:ffff888125466000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000558a3b3124f0 CR3: 000000002a35a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:342 [inline]
 smp_call_function_many_cond+0xcfd/0x12c0 kernel/smp.c:877
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
 flush_tlb_mm_range+0x5c3/0x10c0 arch/x86/mm/tlb.c:1472
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:505 [inline]
 tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:404
 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:530
 unmap_region+0x2a5/0x330 mm/vma.c:488
 vms_clear_ptes mm/vma.c:1284 [inline]
 vms_complete_munmap_vmas+0x493/0xc60 mm/vma.c:1326
 do_vmi_align_munmap+0x3b7/0x4b0 mm/vma.c:1585
 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1633
 __vm_munmap+0x22c/0x3d0 mm/vma.c:3254
 __do_sys_munmap mm/mmap.c:1078 [inline]
 __se_sys_munmap mm/mmap.c:1075 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1075
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdfcb044097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007fff4fb790a8 EFLAGS: 00000206 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000558a3b2dbbf0 RCX: 00007fdfcb044097
RDX: 0000000000000000 RSI: 00000000009480e8 RDI: 00007fdfca000000
RBP: 0000558a3b2db910 R08: 0000558a3b2ee140 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000206 R12: 00005589ff8ac588
R13: 00007fff4fb79130 R14: 0000000000000000 R15: 0000000000000000
 </TASK>