rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (18 ticks this GP) idle=9af4/1/0x4000000000000000 softirq=93475/93477 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=74065, q=67 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13950 Comm: syz.5.2073 Not tainted 6.16.0-rc1-syzkaller-00203-g4774cfe3543a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_preemption_disabled+0x25/0xe0 lib/smp_processor_id.c:56
Code: 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d 85 ac 4c 08 65 8b 05 7a ac 4c 08 a9 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d <41> 5c e9 94 de 02 00 9c 58 f6 c4 02 74 ea 48 89 fd 65 48 8b 05 3a
RSP: 0018:ffffc90000007db8 EFLAGS: 00000082
RAX: 0000000000000000 RBX: ffff8880b8427c98 RCX: ffffffff81a8e2f1
RDX: 1ffff1100a490a6d RSI: ffffffff8c157520 RDI: ffffffff8c157560
RBP: 0000000000000046 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff81a8e979
R13: 1856c9cb85b2715c R14: ffff888052485340 R15: ffffffff8992b740
FS:  00007fee100296c0(0000) GS:ffff888124754000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f2d9ff8 CR3: 000000007b9e7000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:745
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x201/0x2f0 kernel/locking/lockdep.c:5882
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
 _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:194
 __run_hrtimer kernel/time/hrtimer.c:1757 [inline]
 __hrtimer_run_queues+0x529/0xad0 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:unix_dgram_recvmsg+0x0/0x110 net/unix/af_unix.c:2596
Code: 48 8b 7c 24 10 e8 50 f5 fc f7 e9 61 f7 ff ff e8 76 f5 fc f7 e9 15 f7 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 41 56 41 55 41 89 cd 41 54 49 89 d4 55 48 89 f5 53 48
RSP: 0018:ffffc90010e279f8 EFLAGS: 00000246
RAX: ffffffff8a25f6f0 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffc90010e27d98 RDI: ffff88807c406c00
RBP: ffffc90010e27d98 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000007c55 R11: 0000000000000001 R12: ffff88807c406c00
R13: 00002000001f1600 R14: ffffc90010e27ddc R15: 0000000000000002
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2784
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828
 do_recvmmsg+0x2fe/0x750 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013
 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: 0033:0x7fee0f18e929
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:00007fee10029038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fee0f3b6080 RCX: 00007fee0f18e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007fee0f210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fee0f3b6080 R15: 00007ffc0ad165b8
 </TASK>
rcu: rcu_preempt kthread starved for 10506 jiffies! g74065 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:28744 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+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 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: 6055 Comm: kworker/u8:13 Not tainted 6.16.0-rc1-syzkaller-00203-g4774cfe3543a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xd94/0x1510 kernel/smp.c:885
Code: 83 e5 07 4d 01 e6 41 83 c5 03 e8 b7 1b 0c 00 f3 90 41 0f b6 06 41 38 c5 7c 08 84 c0 0f 85 6f 05 00 00 8b 43 08 31 ff 83 e0 01 <89> c5 89 c6 e8 d3 16 0c 00 85 ed 75 d3 e8 8a 1b 0c 00 e8 85 1b 0c
RSP: 0018:ffffc9000c1878a0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffff8880b8443ba0 RCX: ffffffff81b0005d
RDX: ffff888030664880 RSI: ffffffff81b00039 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000
R13: 0000000000000003 R14: ffffed1017088775 R15: ffff8880b853cf40
FS:  0000000000000000(0000) GS:ffff888124854000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2d049b CR3: 000000000e382000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 on_each_cpu include/linux/smp.h:71 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2660 [inline]
 smp_text_poke_batch_finish+0x27b/0xdb0 arch/x86/kernel/alternative.c:2870
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x376/0x550 kernel/jump_label.c:919
 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate mm/kfence/core.c:850 [inline]
 toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:842
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>