rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10505 jiffies, g=56517, q=262 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295072875-4295062373), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g56517 f0x2 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:27336 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </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: 13892 Comm: syz.2.1746 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__lock_acquire+0x1bcd/0x7c80 kernel/locking/lockdep.c:5168
Code: 09 45 31 f6 49 b8 00 00 00 00 00 fc ff df 48 c7 84 24 20 01 00 00 0e 36 e0 45 48 8b 84 24 f0 00 00 00 42 c7 04 00 00 00 00 00 <4a> c7 44 00 0b 00 00 00 00 42 c7 44 00 17 00 00 00 00 42 c6 44 00
RSP: 0018:ffffc900001f0900 EFLAGS: 00000093
RAX: 1ffff9200003e144 RBX: ffff888023db46d8 RCX: ffffffff81670c00
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da7508
RBP: ffffc900001f0b48 R08: dffffc0000000000 R09: 1ffffffff21b4ea1
R10: dffffc0000000000 R11: fffffbfff21b4ea2 R12: d6bf87c490213bdc
R13: ffff888023db3c00 R14: 0000000000000001 R15: ffff888023db4728
FS:  00007f89203d86c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f94f55156c0 CR3: 0000000066f05000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xa3/0xe0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1754 [inline]
 __hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1814
 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5254
Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 e9 f6 04 00 00 4c 8b 75 d0 4c 89 e7 e8 80 b3 1b 09 e8 7b a0 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc9000b70f1f8 EFLAGS: 00000282
RAX: 0aa5df9ed901e500 RBX: 0000000000000000 RCX: 0aa5df9ed901e500
RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc63c0
RBP: ffffc9000b70f250 R08: ffffffff90da75af R09: 1ffffffff21b4eb5
R10: dffffc0000000000 R11: fffffbfff21b4eb6 R12: ffff888023db3c00
R13: dffffc0000000000 R14: ffff88807a8b1e00 R15: ffff8880b8f3ccc8
 context_switch kernel/sched/core.c:5383 [inline]
 __schedule+0x14da/0x44d0 kernel/sched/core.c:6699
 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
 preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xfa/0x110 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x11f/0x190 kernel/sched/wait.c:213
 __unix_dgram_recvmsg+0x49c/0xd60 net/unix/af_unix.c:2437
 sock_recvmsg_nosec+0x82/0xd0 net/socket.c:1046
 ____sys_recvmsg+0x49b/0x5b0 net/socket.c:2812
 ___sys_recvmsg+0x1b6/0x510 net/socket.c:2856
 do_recvmmsg+0x360/0x7d0 net/socket.c:2950
 __sys_recvmmsg net/socket.c:3029 [inline]
 __do_sys_recvmmsg net/socket.c:3052 [inline]
 __se_sys_recvmmsg net/socket.c:3045 [inline]
 __x64_sys_recvmmsg+0x191/0x240 net/socket.c:3045
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f891f58eec9
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:00007f89203d8038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f891f7e6090 RCX: 00007f891f58eec9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f891f611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f891f7e6128 R14: 00007f891f7e6090 R15: 00007fffcdda18c8
 </TASK>