rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=5b5/1/0x4000000000000000 softirq=10396/10396 fqs=0 
	(detected by 0, t=10504 jiffies, g=12701, q=738)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5228 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:find_held_lock kernel/locking/lockdep.c:5113 [inline]
RIP: 0010:__lock_release kernel/locking/lockdep.c:5300 [inline]
RIP: 0010:lock_release+0x1d1/0x870 kernel/locking/lockdep.c:5643
Code: 04 00 00 41 8b 0e 85 c9 0f 84 10 02 00 00 4c 89 64 24 40 4c 89 34 24 4c 89 7c 24 20 44 8d 79 ff 48 8d 9f f0 0a 00 00 4d 63 f7 <48> 89 4c 24 28 83 f9 32 0f 83 ca 04 00 00 4b 8d 04 b6 4c 8d 24 c3
RSP: 0018:ffffc90000dd0b40 EFLAGS: 00000006
RAX: 0000000000000000 RBX: ffff88802c0928b0 RCX: 0000000000000003
RDX: 0000000000000000 RSI: ffffffff8a0b29e0 RDI: ffff88802c091dc0
RBP: ffffc90000dd0c60 R08: dffffc0000000000 R09: fffffbfff1ad26b6
R10: fffffbfff1ad26b6 R11: 1ffffffff1ad26b5 R12: 1ffff11005812515
R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000002
FS:  00007f37309de6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005568470d0cd8 CR3: 0000000067f88000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:404 [inline]
 advance_sched+0x687/0x940 net/sched/sch_taprio.c:765
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 be 9a d2 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d6 22 a6 f7 65 8b 05 67 20 57 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900032aee00 EFLAGS: 00000206
RAX: 76f02ed751235100 RBX: 0000000000000a06 RCX: 76f02ed751235100
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001
RBP: ffffc900032aee90 R08: dffffc0000000000 R09: fffffbfff1ff5432
R10: fffffbfff1ff5432 R11: 1ffffffff1ff5431 R12: dffffc0000000000
R13: 0000001dc1a6601f R14: ffff88802bc69ae8 R15: 1ffff92000655dc0
 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
 taprio_change+0x3ff2/0x4ed0 net/sched/sch_taprio.c:1620
 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1255
 tc_modify_qdisc+0xaa1/0x1770 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500
 __sys_sendmsg net/socket.c:2529 [inline]
 __do_sys_sendmsg net/socket.c:2538 [inline]
 __se_sys_sendmsg+0x190/0x250 net/socket.c:2536
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f373176eb69
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:00007f37309de038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3731995fa0 RCX: 00007f373176eb69
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007f37317f1df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3731995fa0 R15: 00007fffb25871a8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10503 jiffies! g12701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=6817
rcu: rcu_preempt kthread starved for 10504 jiffies! g12701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:28064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5228 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:debug_smp_processor_id+0x0/0x10 lib/smp_processor_id.c:60
Code: 12 8a e8 43 01 00 00 65 c7 05 38 5d 61 76 00 00 00 00 48 c7 c7 60 dc 12 8a e8 2c 01 00 00 65 ff 0d 21 5d 61 76 5b c3 00 00 cc <48> c7 c7 a0 e7 59 8a 48 c7 c6 e0 e7 59 8a eb 00 55 41 57 41 56 53
RSP: 0018:ffffc90000dd0b38 EFLAGS: 00000087
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815c7c29
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d6935a8
RBP: ffffc90000dd0c70 R08: dffffc0000000000 R09: fffffbfff1ad26b6
R10: fffffbfff1ad26b6 R11: 1ffffffff1ad26b5 R12: ffff88802bc69ae8
R13: dffffc0000000000 R14: ffff88802bc69800 R15: 1ffff920001ba178
FS:  00007f37309de6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005568470d0cd8 CR3: 0000000067f88000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0xba/0x870 kernel/locking/lockdep.c:5634
 rcu_read_unlock include/linux/rcupdate.h:773 [inline]
 advance_sched+0x7d0/0x940 net/sched/sch_taprio.c:771
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x53d/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 be 9a d2 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d6 22 a6 f7 65 8b 05 67 20 57 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900032aee00 EFLAGS: 00000206
RAX: 76f02ed751235100 RBX: 0000000000000a06 RCX: 76f02ed751235100
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001
RBP: ffffc900032aee90 R08: dffffc0000000000 R09: fffffbfff1ff5432
R10: fffffbfff1ff5432 R11: 1ffffffff1ff5431 R12: dffffc0000000000
R13: 0000001dc1a6601f R14: ffff88802bc69ae8 R15: 1ffff92000655dc0
 spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
 taprio_change+0x3ff2/0x4ed0 net/sched/sch_taprio.c:1620
 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1255
 tc_modify_qdisc+0xaa1/0x1770 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0x7ff/0xe90 net/core/rtnetlink.c:5684
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:706 [inline]
 __sock_sendmsg net/socket.c:718 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500
 __sys_sendmsg net/socket.c:2529 [inline]
 __do_sys_sendmsg net/socket.c:2538 [inline]
 __se_sys_sendmsg+0x190/0x250 net/socket.c:2536
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f373176eb69
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:00007f37309de038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3731995fa0 RCX: 00007f373176eb69
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007f37317f1df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3731995fa0 R15: 00007fffb25871a8
 </TASK>