rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=547c/0/0x1 softirq=38805/38805 fqs=2
rcu: 	(detected by 0, t=10502 jiffies, g=42517, q=585 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 07/24/2026
RIP: 0010:IS_ERR include/linux/err.h:78 [inline]
RIP: 0010:debug_object_activate+0x1f8/0x420 lib/debugobjects.c:880
Code: 00 74 08 48 89 ef e8 57 69 4d fd 48 8b 55 00 48 39 d3 0f 92 c0 48 8d 8a 00 80 00 00 48 39 cb 0f 93 c1 08 c1 0f 84 1f 01 00 00 <49> 81 fd 00 f0 ff ff 77 45 49 8d 6d 10 49 89 ef 49 c1 ef 03 43 0f
RSP: 0018:ffffc90000a18d08 EFLAGS: 00000046
RAX: 1ffff1100407ec96 RBX: ffff8880779d4300 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a18c60
RBP: ffffffff9abe9d50 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014318c R12: ffff8880203f64b0
R13: ffff8880203f6498 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124dd1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc824c22060 CR3: 000000004fd9e000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 debug_hrtimer_activate kernel/time/hrtimer.c:486 [inline]
 debug_activate kernel/time/hrtimer.c:529 [inline]
 enqueue_hrtimer+0xa9/0x2c0 kernel/time/hrtimer.c:1136
 __run_hrtimer kernel/time/hrtimer.c:2083 [inline]
 __hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2124
 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2243
 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 4c 8f 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 33 41 24 00 fb f4 <e9> 8c 08 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc900001a7e40 EFLAGS: 00000242
RAX: 00000000000528e9 RBX: ffffffff819baed0 RCX: 8000000000000001
RDX: 0000000000000001 RSI: ffffffff8e477774 RDI: ffffffff8c6d9c80
RBP: ffffc900001a7f10 R08: ffff8880b8733a1b R09: 1ffff110170e6743
R10: dffffc0000000000 R11: ffffed10170e6744 R12: 0000000000000000
R13: 1ffff11003cd2bb8 R14: 1ffff92000034fd0 R15: dffffc0000000000
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x2e0/0x540 kernel/sched/idle.c:355
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x157
 </TASK>
rcu: rcu_preempt kthread starved for 9862 jiffies! g42517 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27752 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:7276
 __schedule_loop kernel/sched/core.c:7353 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7368
 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: 0 UID: 0 PID: 5611 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:check_kcov_mode kernel/kcov.c:190 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4f/0x80 kernel/kcov.c:213
Code: 01 00 0f 81 fe 00 01 00 00 40 0f 95 c6 81 fa 00 00 00 10 0f 93 c2 40 08 f2 75 35 83 b9 3c 17 00 00 00 74 2c 8b 91 10 17 00 00 <83> fa 02 75 21 48 8b 91 18 17 00 00 48 8b 32 48 8d 7e 01 8b 89 14
RSP: 0018:ffffc90003a8f318 EFLAGS: 00000246
RAX: ffffffff81bb7b8e RBX: ffff8880b87414c8 RCX: ffff8880123cddc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003a8f470 R08: ffff8880123cf35f R09: 1ffff11002479e6b
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170e8299
R13: 0000000000000001 R14: ffff8880b87414c0 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888124cd1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33f23ffc CR3: 0000000079d20000 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
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
 tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549
 free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
 exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300
 __mmput+0x118/0x420 kernel/fork.c:1193
 exit_mm+0x221/0x2d0 kernel/exit.c:617
 do_exit+0x6cd/0x2360 kernel/exit.c:999
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1154
 get_signal+0x121b/0x12c0 kernel/signal.c:3051
 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
 do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde777592d7
Code: Unable to access opcode bytes at 0x7fde777592ad.
RSP: 002b:00007ffc1e3c2510 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000555561a1c500 RCX: 00007fde777592d7
RDX: 0000000040000000 RSI: 00007ffc1e3c256c RDI: ffffffffffffffff
RBP: 00007ffc1e3c256c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffc1e3c27c8 R15: 0000000000000000
 </TASK>