syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=c394/1/0x4000000000000000 softirq=43420/43421 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=40393, q=1976 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10892 Comm: syz.5.2088 Not tainted 6.13.0-rc7-syzkaller-00189-g595523945be0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:733 [inline]
RIP: 0010:rcu_is_watching+0x6/0xb0 kernel/rcu/tree.c:736
Code: b0 e0 6d 03 eb cd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 65 ff 05 a8 c4 7e 7e e8 fb 37 3c 0a 89 c3 83 f8 08 73 7a
RSP: 0018:ffffc90000007b10 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff817ad780
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90185a70
RBP: ffffc90000007c50 R08: ffffffff90185a77 R09: 1ffffffff2030b4e
R10: dffffc0000000000 R11: fffffbfff2030b4f R12: 1ffff92000000f70
R13: ffffffff89c62044 R14: ffff88806bbc7400 R15: dffffc0000000000
FS:  00007f3580c2d6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c305c43 CR3: 0000000064440000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0xbf/0xa30 kernel/locking/lockdep.c:5860
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x9b4/0xca0 net/sched/sch_taprio.c:981
 __run_hrtimer kernel/time/hrtimer.c:1739 [inline]
 __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1803
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4a e9 b6 f5 48 89 df e8 82 30 b8 f5 e8 1d 3f e3 f5 fb bf 01 00 00 00 <e8> a2 95 a9 f5 65 8b 05 e3 e6 3f 74 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc9000215fd00 EFLAGS: 00000286
RAX: ce78469bed9a5400 RBX: ffff88806bb0a888 RCX: ffffffff9a378903
RDX: dffffc0000000000 RSI: ffffffff8c0a98e0 RDI: 0000000000000001
RBP: 00000000ffffff83 R08: ffffffff90185a77 R09: 1ffffffff2030b4e
R10: dffffc0000000000 R11: fffffbfff2030b4f R12: ffff88806bb0a800
R13: 7fffffffffffffff R14: 0000000000000003 R15: ffff88806bb0a880
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 do_timerfd_settime+0xccf/0xfb0 fs/timerfd.c:523
 __do_sys_timerfd_settime fs/timerfd.c:569 [inline]
 __se_sys_timerfd_settime fs/timerfd.c:560 [inline]
 __x64_sys_timerfd_settime+0x16f/0x220 fs/timerfd.c:560
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f357fd85d29
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:00007f3580c2d038 EFLAGS: 00000246 ORIG_RAX: 000000000000011e
RAX: ffffffffffffffda RBX: 00007f357ff75fa0 RCX: 00007f357fd85d29
RDX: 0000000020000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007f357fe01b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f357ff75fa0 R15: 00007fff8e0a09e8
 </TASK>
rcu: rcu_preempt kthread starved for 10505 jiffies! g40393 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:26264 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc7-syzkaller-00189-g595523945be0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: iou_exit io_ring_exit_work
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 c6 e6 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 71 e2 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 55 e2
RSP: 0018:ffffc90000bc75e0 EFLAGS: 00000293
RAX: ffffffff81938fcb RBX: 1ffff110170c8c65 RCX: ffff888021a8da00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000bc77e0 R08: ffffffff81938f9a R09: 1ffffffff284e310
R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000
R13: ffff8880b8646328 R14: ffff8880b873f940 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff67116b7e0 CR3: 000000000e736000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2114 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324
 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 __static_key_slow_dec_cpuslocked+0xc4/0x110 kernel/jump_label.c:315
 __static_key_slow_dec kernel/jump_label.c:321 [inline]
 static_key_slow_dec+0x51/0xa0 kernel/jump_label.c:336
 io_ring_ctx_free+0xb9b/0xdb0 io_uring/io_uring.c:2754
 io_ring_exit_work+0x80f/0x8a0 io_uring/io_uring.c:2964
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
 worker_thread+0x870/0xd30 kernel/workqueue.c:3398
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>