rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=dc84/1/0x4000000000000000 softirq=16081/16081 fqs=0
rcu: (detected by 0, t=10506 jiffies, g=14977, q=333 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5899 Comm: rm Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:mark_usage kernel/locking/lockdep.c:4674 [inline]
RIP: 0010:__lock_acquire+0x6b7/0x2cf0 kernel/locking/lockdep.c:5191
Code: 99 0d 00 00 41 8b 45 20 a9 00 00 18 00 0f 84 bc 00 00 00 4c 8b 74 24 08 4c 89 f7 4c 89 ee ba 08 00 00 00 e8 5b 44 00 00 31 ed <85> c0 0f 84 6d 0d 00 00 83 3d fa 8a a2 18 00 75 13 48 63 44 24 18
RSP: 0018:ffffc90000a08b40 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff88802fc049d0 RCX: ffffffff93e1a370
RDX: 0000000000000008 RSI: ffff88802fc049b0 RDI: ffff88802fc03d80
RBP: 0000000000000000 R08: ffffffff84bc7223 R09: ffffffff9a656b68
R10: dffffc0000000000 R11: fffff520001411ac R12: 0000000000000002
R13: ffff88802fc049b0 R14: ffff88802fc03d80 R15: 0000000000000004
FS: 0000000000000000(0000) GS:ffff888125393000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f88302f1890 CR3: 0000000011ca4000 CR4: 0000000000350ef0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_activate+0x83/0x580 lib/debugobjects.c:835
debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
debug_activate kernel/time/hrtimer.c:528 [inline]
enqueue_hrtimer+0xa9/0x2c0 kernel/time/hrtimer.c:1109
__run_hrtimer kernel/time/hrtimer.c:1946 [inline]
__hrtimer_run_queues+0x4d2/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:867 [inline]
RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
RIP: 0010:unwind_next_frame+0x1b6f/0x2550 arch/x86/kernel/unwind_orc.c:709
Code: 03 01 4c 8b 7c 24 50 4c 8b 6c 24 20 41 0f b6 44 2d 00 84 c0 0f 85 81 02 00 00 41 c7 06 00 00 00 00 31 db e8 73 dd 30 0a 85 c0 <74> 3a e8 8a c9 33 00 84 c0 75 31 e8 61 dd 30 0a 85 c0 74 28 80 3d
RSP: 0018:ffffc90004147078 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff916c2c01 RCX: ffff88802fc03d80
RDX: ffffc90004147101 RSI: dffffc0000000000 RDI: ffffc90004147150
RBP: dffffc0000000000 R08: ffffc90004147f38 R09: ffffc90004147198
R10: dffffc0000000000 R11: fffff52000828e35 R12: ffffc90004147f48
R13: ffffc90004140000 R14: ffffc90004147148 R15: ffffffff8176e256
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
__slab_free+0x274/0x2c0 mm/slub.c:5608
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4569 [inline]
slab_alloc_node mm/slub.c:4898 [inline]
kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4905
vm_area_alloc+0x24/0x140 mm/vma_init.c:32
__mmap_new_vma mm/vma.c:2547 [inline]
__mmap_region mm/vma.c:2771 [inline]
mmap_region+0x11c6/0x22a0 mm/vma.c:2856
do_mmap+0xc39/0x10c0 mm/mmap.c:560
vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f88305ed242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007ffcb060b1c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f88305ed242
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 0000000000000000
RBP: 0000000000000022 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000002000
R13: 0000000000000000 R14: 00007f88305c10c0 R15: 00007f883050655b
rcu: rcu_preempt kthread starved for 10506 jiffies! g14977 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:27968 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
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: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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 5901 Comm: syz-executor.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 7a 05 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 25 01 0c 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 0a 01 0c 00 eb e5 44 89
RSP: 0018:ffffc900040c7580 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b863c148 RCX: ffff88802fc01ec0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900040c76c0 R08: ffffffff903098f7 R09: 1ffffffff206131e
R10: dffffc0000000000 R11: fffffbfff206131f R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125293000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555ca11ecde0 CR3: 0000000032e5f000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__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+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
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+0xf9/0x230 mm/mmu_gather.c:549
exit_mmap+0x498/0x9e0 mm/mmap.c:1313
__mmput+0x118/0x430 kernel/fork.c:1178
exit_mm+0x18e/0x250 kernel/exit.c:581
do_exit+0x6a2/0x22c0 kernel/exit.c:963
do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
get_signal+0x1284/0x1330 kernel/signal.c:3037
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__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:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f509d66e3b9
Code: Unable to access opcode bytes at 0x7f509d66e38f.
RSP: 002b:00007f509e470138 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f509d7abf88 RCX: 00007f509d66e3b9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f509d7abf88
RBP: 00007f509d7abf80 R08: 00007f509e470cdc R09: 00007f509e470cdc
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f509d7abf8c
R13: 000000000000000b R14: 00007fff597de850 R15: 00007fff597de938