rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 ticks this GP) idle=79b4/1/0x4000000000000000 softirq=51812/51812 fqs=2
rcu: (detected by 1, t=10502 jiffies, g=57309, q=172 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14054 Comm: syz.7.1740 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:mark_lock+0xe2/0x320 kernel/locking/lockdep.c:4656
Code: 03 42 0f b6 04 28 84 c0 0f 85 06 02 00 00 83 3d 13 3f 83 15 00 74 36 45 31 ff 49 83 c7 60 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 ff e8 54 35 75 00 b8 01 00 00 00 45 85 27 74 50 48 83
RSP: 0018:ffffc90000007880 EFLAGS: 00000046
RAX: 1ffffffff20e23de RBX: ffff8880781e1e00 RCX: ffffffff8167b534
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da8500
RBP: 0000000000000009 R08: ffffffff90da8507 R09: 1ffffffff21b50a0
R10: dffffc0000000000 R11: fffffbfff21b50a1 R12: 0000000000000200
R13: dffffc0000000000 R14: ffff8880781e28e0 R15: ffffffff90711ef0
FS: 00005555784c0500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005592eb7020b8 CR3: 000000005fe1a000 CR4: 00000000003506f0
Call Trace:
mark_usage kernel/locking/lockdep.c:4599 [inline]
__lock_acquire+0xd49/0x7c80 kernel/locking/lockdep.c:5091
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock include/linux/rcupdate.h:786 [inline]
advance_sched+0xa15/0xc80 net/sched/sch_taprio.c:1001
__run_hrtimer kernel/time/hrtimer.c:1750 [inline]
__hrtimer_run_queues+0x51e/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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1385
Code: 0f 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 42 0c 11 09 66 90 41 57 41 56 53 eb 11 e8 74 b4 1a 09 e8 1f 32 2e 00 fb 5b <41> 5e 41 5f c3 f3 0f 1e fa 49 be 00 00 00 00 00 fc ff df 49 89 ff
RSP: 0018:ffffc9000e9779a8 EFLAGS: 00000286
RAX: 4c0a5e2961ad9700 RBX: ffff8880b8e3cf48 RCX: 4c0a5e2961ad9700
RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6b00
RBP: ffffc9000e977bb0 R08: ffffffff8e4a8d6f R09: 1ffffffff1c951ad
R10: dffffc0000000000 R11: fffffbfff1c951ae R12: dffffc0000000000
R13: ffff8880b8e3c200 R14: dffffc0000000000 R15: ffff8880b8e3cf48
__schedule+0x171e/0x44d0 kernel/sched/core.c:6703
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:694
RIP: 0010:futex_wait+0x4/0x530 kernel/futex/waitwake.c:633
Code: 41 5d 41 5e 41 5f 5d c3 e8 c9 1c 0b 00 eb bc e8 c2 1c 0b 00 eb b1 e8 db 59 f4 08 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec a0 01
RSP: 0018:ffffc9000e977d38 EFLAGS: 00000293
RAX: ffffffff8179eb82 RBX: 1ffff92001d2efb0 RCX: ffffc9000e977e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f0cd35e609c
RBP: ffffc9000e977e08 R08: 00000000ffffffff R09: 000000000000000d
R10: 000000000000000d R11: 0000000000000000 R12: 0000000000000000
R13: ffffc9000e977da0 R14: 0000000000000000 R15: dffffc0000000000
do_futex+0x2ff/0x3e0 kernel/futex/syscalls.c:106
__do_sys_futex kernel/futex/syscalls.c:183 [inline]
__se_sys_futex+0x36f/0x3f0 kernel/futex/syscalls.c:164
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: 0033:0x7f0cd338f6c9
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:00007ffe9d3e2fd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000137b1a RCX: 00007f0cd338f6c9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0cd35e609c
RBP: 0000000000000032 R08: 0000000000745d1e R09: 000000179d3e32cf
R10: 00007ffe9d3e30d0 R11: 0000000000000246 R12: 00007f0cd35e609c
R13: 00007ffe9d3e30d0 R14: 0000000000137b4c R15: 00007ffe9d3e30f0
rcu: rcu_preempt kthread starved for 10497 jiffies! g57309 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:26920 pid:17 ppid:2 flags:0x00004000
Call Trace:
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 8129 Comm: kworker/u4:14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xddf/0x1130 kernel/smp.c:855
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 da d6 0a 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 15 d3 0a 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 f9 d2
RSP: 0018:ffffc9000e3ef780 EFLAGS: 00000293
RAX: ffffffff817abc97 RBX: 1ffff110171c8791 RCX: ffff88802833da00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000e3ef900 R08: ffffffff90da8507 R09: 1ffffffff21b50a0
R10: dffffc0000000000 R11: fffffbfff21b50a1 R12: ffff8880b8e43c88
R13: dffffc0000000000 R14: ffff8880b8f3d348 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3461dff8 CR3: 000000000cb30000 CR4: 00000000003506e0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:2222 [inline]
text_poke_bp_batch+0x318/0x930 arch/x86/kernel/alternative.c:2432
text_poke_flush arch/x86/kernel/alternative.c:2623 [inline]
text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207
static_key_enable+0x1a/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xaa/0x250 mm/kfence/core.c:831
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
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