rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P19549/1:b..l
rcu: (detected by 1, t=10506 jiffies, g=103385, q=334 ncpus=2)
task:syz-executor state:R running task stack:28088 pid:19549 tgid:19549 ppid:17459 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x374/0x2390 arch/x86/kernel/unwind_orc.c:505
Code: ea 48 01 d2 48 01 f2 48 bd 00 00 00 00 00 fc ff df 0f 84 37 01 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 6d 19 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc9000d2ff8f8 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffffffff8fa237ac RCX: ffffffff8fa237b0
RDX: ffffffff9021cd84 RSI: ffffffff9021cd84 RDI: ffffffff8bc07a80
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8df419e0
R10: ffffc9000d2ffa18 R11: ffffffff81ada290 R12: ffffffff9021cd88
R13: ffffffff9021cd89 R14: ffffc9000d2ff9c8 R15: ffffffff8fa237ac
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:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2540 [inline]
slab_free mm/slub.c:6668 [inline]
kmem_cache_free+0x197/0x620 mm/slub.c:6779
do_symlinkat+0x364/0x3c0 fs/namei.c:5555
__do_sys_symlinkat fs/namei.c:5562 [inline]
__se_sys_symlinkat fs/namei.c:5559 [inline]
__x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5559
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8beed8ecc7
RSP: 002b:00007ffd70b0bb68 EFLAGS: 00000206 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8beed8ecc7
RDX: 00007f8beee158c3 RSI: 00000000ffffff9c RDI: 00007f8beee14390
RBP: 00007ffd70b0bbac R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000000000000005f
R13: 00000000000927c0 R14: 000000000010463d R15: 00007ffd70b0bc00
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g103385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=83599
rcu: rcu_preempt kthread starved for 10506 jiffies! g103385 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25816 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 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+0x599/0xb30 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 19550 Comm: syz.1.3581 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:rcu_read_unlock include/linux/rcupdate.h:895 [inline]
RIP: 0010:advance_sched+0xab3/0xc90 net/sched/sch_taprio.c:993
Code: 00 23 74 8c e8 ee fc 2c f8 4c 89 ef e8 f6 88 c6 ff e8 f1 8f e9 01 89 c5 31 ff 89 c6 e8 b6 ef 4f f8 85 ed 74 10 e8 ad d4 35 f8 <84> c0 74 0e e8 64 eb 4f f8 eb 56 e8 5d eb 4f f8 eb 4f e8 c6 8f e9
RSP: 0018:ffffc90000007c70 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffffffff8971c768 RCX: bb651ed7ed889300
RDX: ffff888025cb0000 RSI: ffffffff8bc07ac0 RDI: ffffffff8bc07a80
RBP: 0000000000000001 R08: ffff88805f73319f R09: 1ffff1100bee6633
R10: dffffc0000000000 R11: ffffed100bee6634 R12: ffff88805f733320
R13: ffff88805f733000 R14: 1883a7f8c2242141 R15: ffff8880293a6400
FS: 00007fc2973b46c0(0000) GS:ffff888125e37000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c31e7d2 CR3: 0000000052d7e000 CR4: 00000000003526f0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x51c/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:__raw_write_unlock_irq include/linux/rwlock_api_smp.h:274 [inline]
RIP: 0010:_raw_write_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:358
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 aa ad 40 f6 48 89 df e8 c2 2d 41 f6 e8 2d 90 6b f6 fb bf 01 00 00 00 82 14 33 f6 65 8b 05 3b 95 20 07 85 c0 74 07 5b c3 cc cc cc cc
RSP: 0018:ffffc9000d2ef990 EFLAGS: 00000286
RAX: bb651ed7ed889300 RBX: ffffffff8f375f20 RCX: bb651ed7ed889300
RDX: 0000000000000007 RSI: ffffffff8d791132 RDI: 0000000000000001
RBP: ffffc9000d2efa50 R08: ffffffff8f820377 R09: 1ffffffff1f0406e
R10: dffffc0000000000 R11: fffffbfff1f0406f R12: 00000000000018d8
R13: dffffc0000000000 R14: 1ffff92001a5df38 R15: 0000000000000007
netlink_table_ungrab net/netlink/af_netlink.c:441 [inline]
__netlink_kernel_create+0x60c/0x710 net/netlink/af_netlink.c:2058
netlink_kernel_create include/linux/netlink.h:62 [inline]
uevent_net_init+0xec/0x2c0 lib/kobject_uevent.c:783
ops_init+0x35c/0x5c0 net/core/net_namespace.c:137
setup_net+0x110/0x330 net/core/net_namespace.c:446
copy_net_ns+0x3e3/0x570 net/core/net_namespace.c:581
create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3171
__do_sys_unshare kernel/fork.c:3242 [inline]
__se_sys_unshare kernel/fork.c:3240 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3240
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc29658f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc2973b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fc2967e5fa0 RCX: 00007fc29658f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000064040400
RBP: 00007fc296613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc2967e6038 R14: 00007fc2967e5fa0 R15: 00007ffdc071e888