rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=481c/1/0x4000000000000000 softirq=42500/42500 fqs=3
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5273/3:b..l
rcu: (detected by 0, t=10502 jiffies, g=60721, q=233 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10811 Comm: syz.2.1894 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__lock_acquire+0x1c1/0x2630 kernel/locking/lockdep.c:5174
Code: 13 44 09 f0 09 d0 8b 94 24 c8 00 00 00 44 09 c8 c1 e2 14 09 d0 8b 94 24 b8 00 00 00 c1 e2 15 09 d0 8b 53 20 81 e2 ff 1f 00 00 <09> d0 89 43 20 8b 84 24 c0 00 00 00 89 43 24 4c 89 e8 25 ff 1f 00
RSP: 0018:ffffc90000a08c00 EFLAGS: 00000046
RAX: 00000000000c4000 RBX: ffff88802d9155e0 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9b4361f8
RBP: ffff88802d914a00 R08: 0000000000000001 R09: 0000000000080000
R10: ffffffff9b4361f8 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007fd5bd9b46c0(0000) GS:ffff888124473000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbb21887fa8 CR3: 0000000048f0d000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1b1/0x370 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166
debug_object_activate+0x144/0x490 lib/debugobjects.c:835
debug_hrtimer_activate kernel/time/hrtimer.c:485 [inline]
debug_activate kernel/time/hrtimer.c:528 [inline]
enqueue_hrtimer+0x75/0x2f0 kernel/time/hrtimer.c:1109
__run_hrtimer kernel/time/hrtimer.c:1946 [inline]
__hrtimer_run_queues+0x73d/0xa00 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206
Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 0a 37 57 f6 48 89 df e8 e2 86 57 f6 e8 7d 94 83 f6 fb bf 01 00 00 00 e2 58 47 f6 65 8b 05 6b 8f 7d 08 85 c0 74 06 5b e9 51 4a 00 00
RSP: 0018:ffffc90004267378 EFLAGS: 00000202
RAX: 000000000000d49d RBX: ffff888035ec75f8 RCX: 0000000000000080
RDX: 0000000000000000 RSI: ffffffff8df20f3b RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000000008cd
R13: ffffc900042673f0 R14: 0000000000000000 R15: 0000000000000000
spin_unlock_irq include/linux/spinlock.h:402 [inline]
shmem_add_to_page_cache+0x874/0xcd0 mm/shmem.c:928
shmem_alloc_and_add_folio+0x558/0xd40 mm/shmem.c:2001
shmem_get_folio_gfp+0x6ab/0x1900 mm/shmem.c:2564
shmem_fault+0x1f9/0xa20 mm/shmem.c:2765
__do_fault+0x10b/0x440 mm/memory.c:5458
do_read_fault mm/memory.c:5893 [inline]
do_fault+0xa99/0x1750 mm/memory.c:6027
do_pte_missing mm/memory.c:4550 [inline]
handle_pte_fault mm/memory.c:6411 [inline]
__handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549
handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x1178/0x32a0 mm/gup.c:1428
populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860
__mm_populate+0x107/0x3a0 mm/gup.c:1963
mm_populate include/linux/mm.h:4137 [inline]
vm_mmap_pgoff+0x37f/0x470 mm/util.c:586
ksys_mmap_pgoff+0xe4/0x610 mm/mmap.c:606
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5bf79cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd5bd9b4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fd5bfa16180 RCX: 00007fd5bf79cdd9
RDX: b635773f07ebbeea RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007fd5bf832d69 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd5bfa16218 R14: 00007fd5bfa16180 R15: 00007ffdb7522c68
task:dhcpcd state:R running task stack:22536 pid:5273 tgid:5273 ppid:5272 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7189
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513
irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline]
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
irqentry_exit+0x1fe/0x790 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 5b 9e 26 12 83 f8 01 0f 85 28 01 00 00 9c 58 f6 c4 02 0f 85 13 01 00 00 41 f7 c6 00 02 00 00 0f 85 c0 00 00 00 <48> 8b 44 24 10 65 48 2b 05 ad 56 26 12 0f 85 4e 01 00 00 48 83 c4
RSP: 0018:ffffc900037f70b8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e7e54e0 RCX: ffffc900037f70c4
RDX: 0000000000000002 RSI: ffffffff8defba11 RDI: ffffffff8c1c3780
RBP: ffffffff81b7c1ae R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000003af5c R12: ffff888028e82500
R13: ffffc900037f7170 R14: 0000000000000202 R15: 0000000000000003
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
unwind_next_frame+0x3c3/0x2090 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5295 [inline]
__kmalloc_node_track_caller_noprof+0x304/0x850 mm/slub.c:5407
kmemdup_noprof+0x29/0x60 mm/util.c:138
kmemdup_noprof include/linux/fortify-string.h:763 [inline]
sidtab_sid2str_get+0x17a/0x670 security/selinux/ss/sidtab.c:625
sidtab_entry_to_string security/selinux/ss/services.c:1316 [inline]
security_sid_to_context_core+0x35a/0x6d0 security/selinux/ss/services.c:1419
avc_audit_post_callback+0x109/0x900 security/selinux/avc.c:703
common_lsm_audit+0x23f/0x2b0 security/lsm_audit.c:454
slow_avc_audit+0x186/0x210 security/selinux/avc.c:779
avc_audit security/selinux/include/avc.h:131 [inline]
avc_has_perm+0x1a6/0x1e0 security/selinux/avc.c:1198
sock_has_perm+0x253/0x2f0 security/selinux/hooks.c:4928
security_socket_recvmsg+0xa5/0x260 security/security.c:4330
sock_recvmsg+0x4a/0x1f0 net/socket.c:1157
____sys_recvmsg+0x218/0x640 net/socket.c:2918
___sys_recvmsg+0x16a/0x1a0 net/socket.c:2960
__sys_recvmsg+0x16d/0x220 net/socket.c:2993
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc77bb8a407
RSP: 002b:00007ffc5d452700 EFLAGS: 00000202 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fc77bb00780 RCX: 00007fc77bb8a407
RDX: 0000000000000000 RSI: 00007ffc5d452790 RDI: 0000000000000010
RBP: 00007ffc5d454bd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055f86449d870
R13: 00007ffc5d452850 R14: 00007ffc5d45279c R15: 00007ffc5d454980
rcu: rcu_preempt kthread starved for 10496 jiffies! g60721 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:27224 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x10e9/0x6820 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 140 Comm: kworker/u8:6 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x1700 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 79 83 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 63 0f 00 00 8b 45 08 31
RSP: 0018:ffffc90002d97870 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81fc0fcd
RDX: ffff888020334a00 RSI: ffffffff81fc0fa7 RDI: ffff888020334a00
RBP: ffff8880b8540f40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a81e9 R14: 0000000000000001 R15: ffff8880b843c5c0
FS: 0000000000000000(0000) GS:ffff888124373000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000007080 CR3: 000000000e596000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 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+0x337/0xc60 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
jump_label_update+0x37a/0x550 kernel/jump_label.c:910
static_key_enable_cpuslocked+0x1bc/0x270 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
toggle_allocation_gate mm/kfence/core.c:906 [inline]
toggle_allocation_gate+0xfe/0x2d0 mm/kfence/core.c:898
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
process_scheduled_works kernel/workqueue.c:3385 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245