rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=5d24/1/0x4000000000000000 softirq=23148/23148 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=17261, q=379 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7476 Comm: syz.2.494 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_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:751
Code: 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 65 ff 05 a3 8e 0f 12 e8 ae fd d4 09 <48> c7 c3 e8 d9 b3 93 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed
RSP: 0018:ffffc90000007cf0 EFLAGS: 00000092
RAX: 0000000000000000 RBX: ffff8880587612c0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8bf2b300 RDI: ffffffff8bf2b340
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888031a22ff0 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f5413f706c0(0000) GS:ffff8881248f6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000002e4030 CR3: 0000000075ff3000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x2cd/0x330 kernel/locking/lockdep.c:5831
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xd9/0xc80 net/sched/sch_taprio.c:930
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x9f/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:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5945
Code: 00 00 b8 ff ff ff ff 65 0f c1 05 5c f0 3a 08 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f e9 87 2c 03 00 45 31 ed eb
RSP: 0018:ffffc9001bd0f968 EFLAGS: 00000282
RAX: 0000000000000046 RBX: 1ffff920037a1f36 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8daa7b4b RDI: ffffffff8bf2b380
RBP: ffffffff8e3c95c0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888031a22ff0 R12: ffff888031a224c0
R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000
 lock_is_held include/linux/lockdep.h:249 [inline]
 __might_resched+0x473/0x5e0 kernel/sched/core.c:8789
 __might_fault+0x83/0x190 mm/memory.c:7172
 _inline_copy_from_user include/linux/uaccess.h:169 [inline]
 _copy_from_user+0x29/0xd0 lib/usercopy.c:18
 copy_from_user include/linux/uaccess.h:223 [inline]
 copy_msghdr_from_user+0x98/0x160 net/socket.c:2522
 recvmsg_copy_msghdr net/socket.c:2778 [inline]
 ___sys_recvmsg+0xdb/0x1a0 net/socket.c:2850
 do_recvmmsg+0x2fe/0x750 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f541318f749
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:00007f5413f70038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f54133e5fa0 RCX: 00007f541318f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f5413213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f54133e6038 R14: 00007f54133e5fa0 R15: 00007ffef1da87c8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g17261 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=6191
rcu: rcu_preempt kthread starved for 10505 jiffies! g17261 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:28320 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>