rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=2afc/1/0x4000000000000000 softirq=166413/166413 fqs=1
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P19404/1:b..l
rcu: (detected by 0, t=10505 jiffies, g=147285, q=381 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5605 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xa/0x20 kernel/kcov.c:314
Code: 00 00 00 e9 58 fe ff ff 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 0c 24 89 f2 <89> fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000a08d70 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff89c6034d
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88807f9c0000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880552c1400 R14: ffff8880552c1400 R15: ffff8880552c1400
FS: 000055555cceb500(0000) GS:ffff888123eee000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555cd0ea88 CR3: 000000005e8d1000 CR4: 00000000003526f0
DR0: 000004000002002c DR1: fffeffffff7fff00 DR2: 0000000080000002
DR3: 0000000000000003 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
taprio_set_budgets+0xcd/0x310 net/sched/sch_taprio.c:670
advance_sched+0x66e/0xd20 net/sched/sch_taprio.c:984
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/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_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 23 ff 7d 12 83 f8 01 0f 85 27 01 00 00 9c 58 f6 c4 02 0f 85 12 01 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 <48> 8b 44 24 10 65 48 2b 05 2d b8 7d 12 0f 85 4d 01 00 00 48 83 c4
RSP: 0018:ffffc900036af898 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8ebe6100 RCX: ffffc900036af8a4
RDX: 0000000000000000 RSI: ffffffff8e17c8fe RDI: ffffffff8c400c80
RBP: ffffffff81b7d6ae R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000019150 R12: ffff88807cf84a80
R13: ffffc900036af950 R14: 0000000000000202 R15: 0000000000000001
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1183 [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
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2705 [inline]
slab_free mm/slub.c:6405 [inline]
kmem_cache_free+0x127/0x6b0 mm/slub.c:6532
free_filename fs/namei.c:152 [inline]
putname+0xb1/0x110 fs/namei.c:311
class_filename_destructor include/linux/fs.h:2559 [inline]
class_filename_maybe_null_destructor include/linux/fs.h:2563 [inline]
vfs_fstatat+0x86/0xe0 fs/stat.c:368
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2318b9c49a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 c7 c2 e8 ff ff ff f7
RSP: 002b:00007ffd1ec4ba18 EFLAGS: 00000286 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007f2318c332ca RCX: 00007f2318b9c49a
RDX: 00007ffd1ec4ba40 RSI: 00007ffd1ec4bad0 RDI: 00000000ffffff9c
RBP: 00007ffd1ec4bad0 R08: 00007ffd1ec4cad0 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000286 R12: 00007ffd1ec4cbc0
R13: 00007f2318c332ca R14: 000000000009da90 R15: 00007ffd1ec4dc90
task:syz-executor state:R running task stack:23496 pid:19404 tgid:19404 ppid:19397 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7413
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
copy_pte_range mm/memory.c:1347 [inline]
copy_pmd_range mm/memory.c:1408 [inline]
copy_pud_range mm/memory.c:1445 [inline]
copy_p4d_range mm/memory.c:1469 [inline]
copy_page_range+0x1c1f/0x5b20 mm/memory.c:1555
dup_mmap+0xd44/0x21b0 mm/mmap.c:1840
dup_mm kernel/fork.c:1543 [inline]
copy_mm kernel/fork.c:1595 [inline]
copy_process+0x4588/0x8030 kernel/fork.c:2289
kernel_clone+0x176/0x9d0 kernel/fork.c:2748
__do_sys_clone+0xd9/0x120 kernel/fork.c:2889
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8af3dc68d2
RSP: 002b:00007ffdef873ae0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffdef873ae0 RCX: 00007f8af3dc68d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffdef873c6c R08: 0000000000000000 R09: 0000000000000001
R10: 0000555588a9a7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000009d9fb R15: 00007ffdef873cc0
rcu: rcu_preempt kthread starved for 10500 jiffies! g147285 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:27880 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
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: 48 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x589/0x16c0 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 b9 95 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 2c 0f 00 00 8b 45 08 31
RSP: 0018:ffffc90000b97878 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81fd3b0d
RDX: ffff8880206d8000 RSI: ffffffff81fd3ae7 RDI: ffff8880206d8000
RBP: ffff8880b8541240 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a8249 R14: 0000000000000001 R15: ffff8880b843c880
FS: 0000000000000000(0000) GS:ffff888123dee000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c312149 CR3: 000000000e992000 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:911 [inline]
toggle_allocation_gate+0xfe/0x2d0 mm/kfence/core.c:903
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
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