rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5859/2:b..l
rcu: (detected by 1, t=13334 jiffies, g=13269, q=440 ncpus=2)
task:syz-executor state:R running task stack:22792 pid:5859 tgid:5859 ppid:5852 task_flags:0x400100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x149b/0x4fd0 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
unlock_task_sighand include/linux/sched/signal.h:756 [inline]
do_send_sig_info kernel/signal.c:1270 [inline]
group_send_sig_info+0x233/0x260 kernel/signal.c:1419
kill_pid_info_type+0xf8/0x1f0 kernel/signal.c:1459
kill_pid_info kernel/signal.c:1473 [inline]
kill_proc_info+0xd9/0x180 kernel/signal.c:1480
kill_something_info kernel/signal.c:1577 [inline]
__do_sys_kill kernel/signal.c:3953 [inline]
__se_sys_kill+0xc4/0x450 kernel/signal.c:3947
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: 0033:0x7f7a2cf2ba37
RSP: 002b:00007ffcfaae3368 EFLAGS: 00000206 ORIG_RAX: 000000000000003e
RAX: ffffffffffffffda RBX: 00007ffcfaae38b0 RCX: 00007f7a2cf2ba37
RDX: 0000000000000003 RSI: 0000000000000009 RDI: 0000000000001747
RBP: 000055555e4e5380 R08: 7fffffffffffffff R09: 3fffffffffffffff
R10: 4000000000000000 R11: 0000000000000206 R12: 00007ffcfaae337c
R13: 000055555e4e1190 R14: 000055555e4e5628 R15: 00007ffcfaae3410
rcu: rcu_preempt kthread starved for 13334 jiffies! g13269 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:27544 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6040 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:taprio_set_budgets+0x16e/0x3b0 net/sched/sch_taprio.c:672
Code: ff df 80 3c 08 00 74 08 4c 89 ef e8 bc a9 b6 f8 4d 89 fe 49 8b 2c 5f 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 08 80 3c 01 00 <4c> 8b 3c 24 74 08 4c 89 ff e8 94 a9 b6 f8 4d 8b 3f 48 89 ef 4c 89
RSP: 0018:ffffc90000007c00 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 1ffff1100a5b7f26
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000010
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f7c R12: 0000000000000000
R13: ffff888052dbfc00 R14: ffff888052dbfc00 R15: ffff888052dbfc00
FS: 0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c000834a00 CR3: 000000000dd3a000 CR4: 00000000003526f0
Call Trace:
advance_sched+0x963/0xc90 net/sched/sch_taprio.c:983
__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:seqcount_lockdep_reader_access+0xed/0x100 include/linux/seqlock.h:75
Code: 00 75 11 e8 35 b2 3e f8 4d 85 f6 75 16 e8 2b b2 3e f8 eb 15 e8 24 b2 3e f8 e8 6f 4d d7 01 4d 85 f6 74 ea e8 15 b2 3e f8 fb 5b <41> 5e e9 3c 2c da 01 cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc90003077910 EFLAGS: 00000293
RAX: ffffffff8982439b RBX: 0000000000000001 RCX: ffff888030865b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003077a70 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff8880b863a080
R13: ffff8880750ade18 R14: 0000000000000200 R15: 0000000000040000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:342 [inline]
gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1548
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