rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=305c/1/0x4000000000000000 softirq=104900/104901 fqs=1
rcu: 	(detected by 1, t=10502 jiffies, g=94133, q=548 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 23237 Comm: syz.5.7975 Not tainted 6.15.0-syzkaller-11802-g1af80d00e1e0 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
RIP: 0010:rcu_is_watching+0x79/0xc0 kernel/rcu/tree.c:746
Code: 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b 03 c1 e8 02 83 e0 01 <65> ff 0d b0 51 2a 12 74 07 5b 5d e9 57 04 df 09 e8 d2 06 8b ff 5b
RSP: 0018:ffffc90000007e00 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff8880b8433228 RCX: ffffffff81a8c678
RDX: 0000000000000000 RSI: ffffffff8c154920 RDI: ffffffff8df1dda0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff9b02eaf0 R12: 0000000000000001
R13: 0000000000000000 R14: ffff888027945340 R15: 0000000000000001
FS:  00007f61c8de96c0(0000) GS:ffff888124765000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c33dfa5 CR3: 0000000060a40000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 trace_hrtimer_start include/trace/events/timer.h:222 [inline]
 debug_activate kernel/time/hrtimer.c:485 [inline]
 enqueue_hrtimer+0x2d3/0x3b0 kernel/time/hrtimer.c:1088
 __run_hrtimer kernel/time/hrtimer.c:1778 [inline]
 __hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:queue_work_on+0x86/0x1f0 kernel/workqueue.c:2397
Code: 38 00 45 84 f6 74 38 e8 b8 46 38 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 16 42 38 00 48 85 db 0f 85 4f 01 00 00 45 31 f6 <e8> 95 46 38 00 44 89 f0 5b 5d 41 5c 41 5d 41 5e e9 05 93 fc 09 e8
RSP: 0018:ffffc9000bda7bd8 EFLAGS: 00000287
RAX: 00000000000003e2 RBX: 0000000000000000 RCX: ffffc9001c219000
RDX: 0000000000080000 RSI: ffffffff8183d086 RDI: 0000000000000007
RBP: 0000000000000200 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000008
R13: ffff88801b87a000 R14: 0000000000000001 R15: 0000000000000000
 queue_work include/linux/workqueue.h:662 [inline]
 ntp_notify_cmos_timer+0xa3/0xc0 kernel/time/ntp.c:676
 do_adjtimex+0x83c/0xaa0 kernel/time/timekeeping.c:2592
 do_clock_adjtime kernel/time/posix-timers.c:1162 [inline]
 __do_sys_clock_adjtime+0x175/0x290 kernel/time/posix-timers.c:1174
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f61c7f8e929
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:00007f61c8de9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000131
RAX: ffffffffffffffda RBX: 00007f61c81b5fa0 RCX: 00007f61c7f8e929
RDX: 0000000000000000 RSI: 0000200000000480 RDI: 0000000000000000
RBP: 00007f61c8010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f61c81b5fa0 R15: 00007ffd6f02da68
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g94133 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27672 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 3463 Comm: kworker/u8:8 Not tainted 6.15.0-syzkaller-11802-g1af80d00e1e0 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: netns cleanup_net
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_single+0x1fb/0x6b0 kernel/smp.c:679
Code: 24 ce 00 00 00 48 89 de e8 82 fa ff ff 41 89 c5 0f 1f 44 00 00 e8 15 07 0c 00 eb 07 e8 0e 07 0c 00 f3 90 8b 9c 24 c8 00 00 00 <31> ff 83 e3 01 89 de e8 39 02 0c 00 85 db 75 e2 e8 f0 06 0c 00 e8
RSP: 0018:ffffc9000cac79c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000011 RCX: ffffffff81b00f67
RDX: ffff8880333c8000 RSI: ffffffff81b00f52 RDI: 0000000000000005
RBP: ffffc9000cac7b20 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 1ffff92001958f40
R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124865000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2478ee CR3: 0000000062b9e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rcu_barrier kernel/rcu/tree.c:3834 [inline]
 rcu_barrier+0x28d/0x6e0 kernel/rcu/tree.c:3771
 cleanup_net+0x419/0x890 net/core/net_namespace.c:693
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>