rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-....: (1 ticks this GP) idle=c79c/1/0x4000000000000000 softirq=154241/154241 fqs=23
rcu: hardirqs softirqs csw/system
rcu: number: 3 18 10
rcu: cputime: 0 0 0 ==> 50900(ms)
rcu: (detected by 1, t=10510 jiffies, g=164721, q=772 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5284 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x8/0x90 kernel/kcov.c:314
Code: 89 44 11 20 c3 cc cc cc cc cc 0f 1f 84 00 00 00 00 00 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 15 38 0a a6 11 65 8b 0d 59 0a a6 11 81 e1 00 01 ff 00 74
RSP: 0018:ffffc90000007d60 EFLAGS: 00000006
RAX: ffffffff81b34943 RBX: 0000000000000000 RCX: ffff88801eaf8000
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 0000000000000000 R08: ffffffff9aa644bb R09: 1ffffffff354c897
R10: dffffc0000000000 R11: fffffbfff354c898 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff88804880c300 R15: 0000000000000000
FS: 00007f9abfa1d780(0000) GS:ffff888124f58000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055579ab83450 CR3: 00000000780e2000 CR4: 00000000003526f0
Call Trace:
cpu_max_bits_warn include/linux/cpumask.h:140 [inline]
cpumask_check include/linux/cpumask.h:147 [inline]
cpumask_test_cpu include/linux/cpumask.h:651 [inline]
cpu_online include/linux/cpumask.h:1233 [inline]
trace_hrtimer_start+0x33/0x200 include/trace/events/timer.h:223
debug_activate kernel/time/hrtimer.c:529 [inline]
enqueue_hrtimer+0xb7/0x2c0 kernel/time/hrtimer.c:1109
__run_hrtimer kernel/time/hrtimer.c:2048 [inline]
__hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d d4 4e 89 0c 48 89 de 5b e9 a3 01 62 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0d 78 0e a6 11 65 8b 15 99 0e a6
RSP: 0018:ffffc900034df620 EFLAGS: 00000286
RAX: 1ffff11006736171 RBX: ffff8880339b0b80 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000028 RDI: 0000000000000028
RBP: 0000000000000000 R08: ffff8880783cb017 R09: 1ffff1100f079602
R10: dffffc0000000000 R11: ffffed100f079603 R12: ffff8880414564f0
R13: ffff8880339b0b88 R14: 1ffff1100f079600 R15: 0000000000000028
__anon_vma_interval_tree_insert mm/interval_tree.c:66 [inline]
anon_vma_interval_tree_insert+0x25e/0x3c0 mm/interval_tree.c:77
anon_vma_clone+0x7a1/0x9e0 mm/rmap.c:357
anon_vma_fork+0x177/0x540 mm/rmap.c:404
dup_mmap+0x970/0x1d90 mm/mmap.c:1803
dup_mm kernel/fork.c:1543 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1595
copy_process+0x1e3e/0x4390 kernel/fork.c:2289
kernel_clone+0x2d7/0x940 kernel/fork.c:2748
__do_sys_clone kernel/fork.c:2889 [inline]
__se_sys_clone kernel/fork.c:2873 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2873
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9abfaf1636
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:00007fff4bd80e30 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff4bd80e38 RCX: 00007f9abfaf1636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fff4bda1380 R08: 0000000000000000 R09: 0000000000000001
R10: 00007f9abfa1da50 R11: 0000000000000246 R12: 00007fff4bd80f70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000555768a1eac0
rcu: rcu_preempt kthread starved for 5056 jiffies! g164721 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:26848 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
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: 1 UID: 0 PID: 8868 Comm: kworker/u8:44 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b0/0x14b0 kernel/smp.c:892
Code: c0 75 73 41 8b 1e 89 de 83 e6 01 31 ff e8 d8 22 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 84 1e 0c 00 eb 37 f3 90 <41> 0f b6 04 1c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 69 1e 0c
RSP: 0018:ffffc900036ef720 EFLAGS: 00000293
RAX: ffffffff81ba5317 RBX: dffffc0000000000 RCX: ffff88807b21be00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900036ef860 R08: ffffffff905789f7 R09: 1ffffffff20af13e
R10: dffffc0000000000 R11: fffffbfff20af13f R12: 1ffff110170c85fd
R13: ffff8880b873c448 R14: ffff8880b8642fe8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125058000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9abfc1ddd0 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5fd/0x1110 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:911
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
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