rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=cc5c/1/0x4000000000000000 softirq=21222/21222 fqs=8
rcu: 	(detected by 1, t=10502 jiffies, g=22033, q=1337 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: rcu_gp process_srcu
RIP: 0010:lock_class_cache_is_valid kernel/locking/lockdep.c:984 [inline]
RIP: 0010:__lock_acquire+0xea/0x2de0 kernel/locking/lockdep.c:5155
Code: 03 48 b9 29 5c 8f c2 f5 28 5c 8f 48 0f af ca 48 0f a3 0d 39 b3 f7 12 73 26 48 8b 0b 48 85 c9 74 1e ba 01 00 00 00 85 f6 75 09 <8b> 50 58 48 83 fa 07 77 0c 48 8b 78 40 48 01 d1 48 39 cf 74 16 45
RSP: 0018:ffffc90000007b50 EFLAGS: 00000046
RAX: ffffffff943be4d0 RBX: ffffffff9aceda78 RCX: ffffffff9abcfa00
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffff9aceda78
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffc90000007d58 R11: fffff52000000fad R12: ffffffff9aceda78
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124ccd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564b596bd540 CR3: 000000007faf6000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
 _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:181
 debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:936
 debug_hrtimer_deactivate kernel/time/hrtimer.c:491 [inline]
 __run_hrtimer kernel/time/hrtimer.c:2042 [inline]
 __hrtimer_run_queues+0x239/0xa10 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:delay_tsc+0x5d/0xd0 arch/x86/lib/delay.c:77
Code: 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 55 bf 01 00 00 00 e8 82 2d b0 f5 65 48 8b 05 fa 78 b0 07 48 85 c0 74 1c f3 90 <bf> 01 00 00 00 e8 19 2c b0 f5 e8 f4 7a 01 00 39 c5 75 0e 0f 01 f9
RSP: 0018:ffffc900000e7908 EFLAGS: 00000286
RAX: 8000000000000000 RBX: 0000000000002af9 RCX: ffffffff9a9e7501
RDX: 0000000000000001 RSI: ffffffff8c6da060 RDI: 00000000ffffffff
RBP: 0000000000000000 R08: ffff8880b8743847 R09: 1ffff110170e8708
R10: dffffc0000000000 R11: ffffffff8be4b6c0 R12: 0000000000000001
R13: 0000000000000001 R14: 0000006877dcb523 R15: 00000000000020ea
 udelay include/asm-generic/delay.h:64 [inline]
 try_check_zero+0x439/0x4c0 kernel/rcu/srcutree.c:1139
 srcu_advance_state kernel/rcu/srcutree.c:1845 [inline]
 process_srcu+0x328/0x16f0 kernel/rcu/srcutree.c:1954
 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
 </TASK>
rcu: rcu_preempt kthread starved for 10484 jiffies! g22033 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:27496 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5526 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7277
 __schedule_loop kernel/sched/core.c:7354 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7369
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 5841 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:37 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:179 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x80 kernel/kcov.c:213
Code: de 5b e9 83 85 64 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 78 5d cd 11 <65> 48 8b 15 78 5d cd 11 f7 c2 00 01 00 ff 74 29 89 d6 81 e6 00 01
RSP: 0018:ffffc90004157418 EFLAGS: 00000202
RAX: ffffffff81bb817e RBX: ffff8880b8643708 RCX: ffff88807f5e8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004157570 R08: ffff88807f5e959f R09: 1ffff1100febd2b3
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170c86e1
R13: 0000000000000000 R14: ffff8880b8643700 R15: 0000000000000001
FS:  000055556b249500(0000) GS:ffff888124dcd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc239556c8 CR3: 000000002669a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:363 [inline]
 csd_lock kernel/smp.c:396 [inline]
 smp_call_function_many_cond+0x63e/0x1500 kernel/smp.c:944
 __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+0x8ff/0x1090 arch/x86/mm/tlb.c:1435
 dup_mmap+0x1758/0x1dc0 mm/mmap.c:1884
 dup_mm kernel/fork.c:1543 [inline]
 copy_mm+0x11a/0x480 kernel/fork.c:1595
 copy_process+0x1e75/0x43e0 kernel/fork.c:2310
 kernel_clone+0x2d7/0x940 kernel/fork.c:2769
 __do_sys_clone kernel/fork.c:2911 [inline]
 __se_sys_clone kernel/fork.c:2895 [inline]
 __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2895
 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: 0033:0x7efc22bc6bd2
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:00007ffe88965df0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe88965df0 RCX: 00007efc22bc6bd2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffe88965f7c R08: 0000000000000000 R09: 0000000000000001
R10: 000055556b2497d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000233c8 R15: 00007ffe88965fd0
 </TASK>