rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (2 ticks this GP) idle=0f34/1/0x4000000000000000 softirq=15683/15683 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=13729, q=285 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5951 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_is_watching+0x67/0xb0 kernel/rcu/tree.c:752
Code: 89 f7 e8 5c 19 80 00 48 c7 c3 d8 46 81 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d 79 13 d9 10 <74> 11 83 e0 04 c1 e8 02 5b 41 5e 41 5f e9 17 73 b5 09 cc e8 11 7b
RSP: 0018:ffffc90000a08c08 EFLAGS: 00000006
RAX: 0000000000030f34 RBX: ffff8880b87336d8 RCX: 0000000000010004
RDX: 0000000000000001 RSI: ffffffff8bc083c0 RDI: ffffffff8bc08380
RBP: ffff88813ffb3460 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000141180 R12: ffff88813ffb3470
R13: ffffffff8497c728 R14: ffffffff8d9aedd8 R15: dffffc0000000000
FS:  000055556354f500(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f23f7bb49e0 CR3: 000000007c04c000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x4b/0x3b0 kernel/locking/lockdep.c:5879
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x1b/0x80 kernel/locking/spinlock.c:194
 debug_object_activate+0x318/0x540 lib/debugobjects.c:836
 debug_hrtimer_activate kernel/time/hrtimer.c:438 [inline]
 debug_activate kernel/time/hrtimer.c:477 [inline]
 enqueue_hrtimer+0x30/0x380 kernel/time/hrtimer.c:1081
 __run_hrtimer kernel/time/hrtimer.c:1794 [inline]
 __hrtimer_run_queues+0x636/0xc30 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic_long_read include/linux/atomic/atomic-instrumented.h:3188 [inline]
RIP: 0010:__mutex_owner kernel/locking/mutex.h:47 [inline]
RIP: 0010:mutex_spin_on_owner+0x27b/0x360 kernel/locking/mutex.c:363
Code: be 08 00 00 00 e8 75 a3 89 00 42 80 7c 35 00 00 74 08 4c 89 e7 e8 f5 a0 89 00 49 f7 04 24 01 00 00 00 0f 85 8c 00 00 00 f3 90 <4c> 89 e7 be 08 00 00 00 e8 48 a3 89 00 42 80 7c 35 00 00 0f 84 90
RSP: 0018:ffffc90003be7088 EFLAGS: 00000246
RAX: 1ffff11005d8f7a0 RBX: ffffffff8f311d70 RCX: ffffffff819d7518
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
RBP: 1ffffffff1e623a4 R08: ffffffff8f311d27 R09: 1ffffffff1e623a4
R10: dffffc0000000000 R11: fffffbfff1e623a5 R12: ffffffff8f311d20
R13: ffffffff8f311d70 R14: dffffc0000000000 R15: ffff888024978000
 mutex_optimistic_spin kernel/locking/mutex.c:480 [inline]
 __mutex_lock_common kernel/locking/mutex.c:618 [inline]
 __mutex_lock+0x311/0x1350 kernel/locking/mutex.c:776
 rtnl_lock net/core/rtnetlink.c:80 [inline]
 rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
 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: 0033:0x7f56a3b915dc
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007f56a3f0f630 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f56a4914620 RCX: 00007f56a3b915dc
RDX: 000000000000002c RSI: 00007f56a4914670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007f56a3f0f684 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f56a4914670 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g13729 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=6960
rcu: rcu_preempt kthread starved for 10502 jiffies! g13729 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:28080 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 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
 </TASK>