rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (3 ticks this GP) idle=16dc/1/0x4000000000000000 softirq=20041/20041 fqs=0 rcu: (detected by 1, t=10502 jiffies, g=13897, q=804 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5528 Comm: dhcpcd Not tainted 6.17.0-rc1-syzkaller-00202-g7de0eebbb4c3 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:preempt_count_add+0x9/0x1a0 kernel/sched/core.c:5816 Code: 19 93 00 eb 8c e9 f1 fe ff ff 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 <49> bf 00 00 00 00 00 fc ff df 48 c7 c0 20 93 ab 99 48 c1 e8 03 42 RSP: 0018:ffffc90000007be0 EFLAGS: 00000046 RAX: f3f3f300f1f1f1f1 RBX: ffffffff99d4dcf0 RCX: 0000000000016b68 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc90000007c98 R08: ffffc90000007cbf R09: 0000000000000000 R10: ffffc90000007cb0 R11: fffff52000000f98 R12: dffffc0000000000 R13: dffffc0000000000 R14: 0000000000000802 R15: 1ffff92000000f80 FS: 00007f89030b9740(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005571df73ba28 CR3: 000000007a11e000 CR4: 00000000003526f0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0x8c/0xf0 kernel/locking/spinlock.c:162 debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline] debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:490 __run_hrtimer kernel/time/hrtimer.c:1729 [inline] __hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 eb e3 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc900038a72b0 EFLAGS: 00000206 RAX: 78e13278fa337100 RBX: 0000000000000000 RCX: 78e13278fa337100 RDX: 0000000000000000 RSI: ffffffff8dba6164 RDI: ffffffff8be33400 RBP: ffffffff81cea1d6 R08: 0000000000000000 R09: ffffffff81cea1d6 R10: ffffc900038a7438 R11: ffffffff81ac3870 R12: 0000000000000002 R13: ffffffff8e139ee0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] is_bpf_text_address+0x47/0x2b0 kernel/bpf/core.c:776 kernel_text_address+0xa5/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 vm_area_dup+0x2b/0x680 mm/vma_init.c:122 dup_mmap+0x90c/0x1ac0 mm/mmap.c:1780 dup_mm kernel/fork.c:1485 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1537 copy_process+0x1706/0x3c00 kernel/fork.c:2175 kernel_clone+0x21e/0x840 kernel/fork.c:2605 __do_sys_clone kernel/fork.c:2748 [inline] __se_sys_clone kernel/fork.c:2732 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2732 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f890318d636 Code: 89 df e8 6d e8 f6 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 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffe1793e370 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffe1793e378 RCX: 00007f890318d636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffe1795e8c0 R08: 0000000000000000 R09: 0000000000000001 R10: 00007f89030b9a10 R11: 0000000000000246 R12: 00007ffe1793e4b0 R13: 0000000000000000 R14: 0000000000000000 R15: 00005571b7845ac0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g13897 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=4293 rcu: rcu_preempt kthread starved for 10502 jiffies! g13897 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27208 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245