rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=32f4/1/0x4000000000000000 softirq=163984/163985 fqs=1
rcu: (detected by 0, t=10502 jiffies, g=143569, q=400 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 25562 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__rb_erase_augmented include/linux/rbtree_augmented.h:228 [inline]
RIP: 0010:rb_erase+0x56/0xe60 lib/rbtree.c:443
Code: 03 80 3c 08 00 74 05 e8 28 45 d2 f6 4d 8b 7d 08 4d 8d 75 10 4c 89 f5 48 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 80 7c 05 00 00 <74> 08 4c 89 f7 e8 00 45 d2 f6 4d 8b 26 4d 85 e4 48 89 5c 24 18 74
RSP: 0018:ffffc90000a08ca8 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880b8728390 RCX: dffffc0000000000
RDX: 0000000000010000 RSI: ffff8880b8728390 RDI: ffff88807989c308
RBP: 1ffff1100f313862 R08: ffffffff8f822077 R09: 1ffffffff1f0440e
R10: dffffc0000000000 R11: fffffbfff1f0440f R12: ffff8880b8728398
R13: ffff88807989c300 R14: ffff88807989c310 R15: 0000000000000000
FS: 0000555557428500(0000) GS:ffff888125f21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f07c0be7dac CR3: 000000008efd8000 CR4: 0000000000350ef0
Call Trace:
rb_erase_cached include/linux/rbtree.h:154 [inline]
timerqueue_del+0xae/0x100 lib/timerqueue.c:57
__remove_hrtimer kernel/time/hrtimer.c:1114 [inline]
__run_hrtimer kernel/time/hrtimer.c:1757 [inline]
__hrtimer_run_queues+0x364/0xc30 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x18ce/0x23d0 arch/x86/kernel/unwind_orc.c:-1
Code: 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 43 0a 00 00 49 0f bf 04 24 48 01 c6 4c 89 f7 48 89 da e8 84 0d 00 00 84 c0 <0f> 84 47 01 00 00 48 bd 00 00 00 00 00 fc ff df 48 8b 44 24 20 0f
RSP: 0018:ffffc900032870d8 EFLAGS: 00000202
RAX: 1ffff92000650e01 RBX: ffffffff90bd67a4 RCX: 0000000000000001
RDX: ffffc900032871e8 RSI: dffffc0000000000 RDI: ffffc90003287f38
RBP: dffffc0000000000 R08: ffffc90003287f38 R09: ffffc900032871f8
R10: dffffc0000000000 R11: fffff52000650e41 R12: ffffc900032871f8
R13: 1ffff92000650e37 R14: ffffc900032871a8 R15: 1ffffffff217acf4
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_noprof+0x41d/0x800 mm/slub.c:5669
kmalloc_noprof include/linux/slab.h:961 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x1c1/0x3b0 security/tomoyo/file.c:771
security_file_open+0xb1/0x270 security/security.c:2636
do_dentry_open+0x34e/0x1420 fs/open.c:939
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:4628 [inline]
path_openat+0x340e/0x3dd0 fs/namei.c:4787
do_filp_open+0x1fa/0x410 fs/namei.c:4814
do_sys_openat2+0x121/0x200 fs/open.c:1430
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1447
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f35f838df90
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 69 95 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 bc 95 02 00 8b 44
RSP: 002b:00007ffe691f35b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f35f838df90
RDX: 0000000000000000 RSI: 00007ffe691f36e0 RDI: 00000000ffffff9c
RBP: 00007ffe691f36e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe691f47d0
R13: 00007f35f8413d7d R14: 00005555574284a8 R15: 0000000000000006
rcu: rcu_preempt kthread starved for 10500 jiffies! g143569 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:27416 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
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+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 24434 Comm: kworker/u8:4 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d a4 ff d9 0b 48 89 de 5b e9 83 fc 5a 00 cc cc cc 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 0c 25 08 f0 7f 92 65 8b 15 a8 f9 be 10 81 e2 00 01 ff 00
RSP: 0018:ffffc90003067698 EFLAGS: 00000202
RAX: ffffffff81b5650d RBX: 1ffff110170e8129 RCX: ffff888052091e80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900030677e0 R08: ffffffff8f822077 R09: 1ffffffff1f0440e
R10: dffffc0000000000 R11: fffffbfff1f0440f R12: ffff8880b8740948
R13: dffffc0000000000 R14: ffff8880b863bb00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125e21000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31216ff8 CR3: 000000000dd3a000 CR4: 0000000000350ef0
Call Trace:
csd_lock_wait kernel/smp.c:342 [inline]
smp_call_function_many_cond+0xcdd/0x1260 kernel/smp.c:877
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
on_each_cpu include/linux/smp.h:71 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline]
smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2921
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+0xad/0x240 mm/kfence/core.c:874
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246