rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=6324/1/0x4000000000000000 softirq=163094/163094 fqs=3
rcu: (detected by 1, t=10502 jiffies, g=165089, q=412 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5083 Comm: dhcpcd-run-hook Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:23 [inline]
RIP: 0010:lock_acquire+0x51/0x350 kernel/locking/lockdep.c:5905
Code: 8b 05 2b 6a f5 12 48 89 44 24 50 0f 1f 44 00 00 65 8b 05 2a 6a f5 12 83 f8 08 0f 83 9b 01 00 00 89 c0 48 0f a3 05 97 a4 d6 0f <73> 0d e8 98 57 09 00 84 c0 0f 84 e2 01 00 00 83 3d a9 d3 d6 0f 00
RSP: 0018:ffffc90000007c58 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9bd079c0
RBP: ffffffff9bd079a0 R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000007d20 R11: fffff52000000fa6 R12: ffffffff9bd079c0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
FS: 00007f6c78fecc80(0000) GS:ffff888123a8b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6c792507e8 CR3: 0000000072600000 CR4: 00000000003526f0
Call Trace:
__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_activate+0xb7/0x420 lib/debugobjects.c:873
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:1137
__run_hrtimer kernel/time/hrtimer.c:2091 [inline]
__hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2132
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2251
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:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947
Code: ff ff ff e8 20 3e 51 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 32 68 f5 12 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 50 54 0a cc 48 8d 3d 87 dc d9
RSP: 0018:ffffc9000360f200 EFLAGS: 00000296
RAX: 58750b9ad96adc00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000e658532b RSI: ffffffff8e6f7dc2 RDI: ffffffff8c6e6780
RBP: ffff88801d363e80 R08: ffffffff81b1e09d R09: 0000000000000000
R10: ffffc9000360f318 R11: ffffffff81b37250 R12: ffffffff8fd5a420
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
is_module_text_address+0x39/0x1e0 kernel/module/main.c:3957
kernel_text_address+0x94/0xe0 kernel/extable.c:119
__kernel_text_address+0xd/0x30 kernel/extable.c:79
unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:385
arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:351 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:377
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4720 [inline]
slab_alloc_node mm/slub.c:5033 [inline]
kmem_cache_alloc_noprof+0x2b4/0x600 mm/slub.c:5047
vm_area_dup+0x28/0x760 mm/vma_init.c:128
dup_mmap+0x8d6/0x1e10 mm/mmap.c:1763
dup_mm kernel/fork.c:1542 [inline]
copy_mm+0x115/0x470 kernel/fork.c:1594
copy_process+0x1ecc/0x44b0 kernel/fork.c:2320
kernel_clone+0x2d7/0x940 kernel/fork.c:2784
__do_sys_clone kernel/fork.c:2926 [inline]
__se_sys_clone kernel/fork.c:2910 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2910
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: 0033:0x7f6c79186636
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:00007fff71504d70 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff71504d78 RCX: 00007f6c79186636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00005556ff586e60 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f6c78fecf50 R11: 0000000000000246 R12: 00005556ff588f70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10496 jiffies! g165089 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:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 5071 Comm: syz.8.8281 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:437
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 7b b6 3a f5 cc
RSP: 0018:ffffc900051f7318 EFLAGS: 00000293
RAX: ffffffff81bc6a3e RBX: ffff8880b8443d68 RCX: ffff88801ff9be80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900051f7470 R08: ffff88801ff9d41f R09: 1ffff11003ff3a83
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170887ad
R13: 0000000000000000 R14: ffff8880b8443d60 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888123b8b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31717ff8 CR3: 000000002b5b4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
csd_lock_wait kernel/smp.c:389 [inline]
csd_lock kernel/smp.c:422 [inline]
smp_call_function_many_cond+0x63e/0x1500 kernel/smp.c:970
__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+0x910/0x10b0 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:461 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:403
tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:529
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+0x1b7/0xa40 mm/mmap.c:1300
__mmput+0x118/0x420 kernel/fork.c:1192
exit_mm+0x18e/0x240 kernel/exit.c:586
do_exit+0x6a8/0x2360 kernel/exit.c:967
do_group_exit+0x22d/0x2f0 kernel/exit.c:1123
get_signal+0x1216/0x12c0 kernel/signal.c:3112
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:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffb1c79e559
Code: Unable to access opcode bytes at 0x7ffb1c79e52f.
RSP: 002b:00007ffb1d6750e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007ffb1ca26098 RCX: 00007ffb1c79e559
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ffb1ca26098
RBP: 00007ffb1ca26090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffb1ca26128 R14: 00007ffcaa170cd0 R15: 00007ffcaa170db8