rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-...!: (10499 ticks this GP) idle=277/1/0x4000000000000000 softirq=10659/10668 fqs=0
(t=10500 jiffies g=13549 q=180)
rcu: rcu_preempt kthread starved for 10500 jiffies! g13549 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27464 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5359 Comm: syz.4.38 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_preemption_disabled+0x3/0x110 lib/smp_processor_id.c:13
Code: c7 c7 00 cd 12 8a e8 2c 01 00 00 65 ff 0d a1 16 5b 76 5b c3 00 00 cc 48 c7 c7 e0 92 59 8a 48 c7 c6 20 93 59 8a eb 00 55 41 57 <41> 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65
RSP: 0018:ffffc90002e7fe28 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88807cb828a8 RCX: d01a4d8b02c46700
RDX: dffffc0000000000 RSI: ffffffff8a0b2860 RDI: ffffffff8a599340
RBP: ffffc90002e7ff00 R08: dffffc0000000000 R09: fffffbfff1ad2dd6
R10: fffffbfff1ad2dd6 R11: 1ffffffff1ad2dd5 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffff1100f970515 R15: ffff88807cb82890
FS: 00007fdc5ba1b6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002006b000 CR3: 000000001d737000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:436 [inline]
lockdep_hardirqs_on_prepare+0x3fc/0x760 kernel/locking/lockdep.c:4279
__exit_to_user_mode kernel/entry/common.c:133 [inline]
syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:309
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdc5c662940
Code: 44 24 20 0f 29 44 24 30 0f 29 44 24 40 48 8b 44 24 08 ff d0 48 83 c4 50 31 c0 5b 5d 41 5c 41 5d 41 5e c3 0f 1f 80 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 c3 66 66 2e 0f 1f
RSP: 002b:00007fdc5ba1ab38 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 00007fdc5c992fa8 RCX: 00007fdc5c7a2d19
RDX: 00007fdc5ba1ab40 RSI: 00007fdc5ba1ac70 RDI: 0000000000000011
RBP: 00007fdc5c992fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdc5c992fac
R13: 0000000000000000 R14: 00007ffd5f27dcf0 R15: 00007ffd5f27ddd8
NMI backtrace for cpu 1
CPU: 1 PID: 5357 Comm: syz.2.37 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x6d8/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 7e db aa f7 48 89 df e8 46 b0 ab f7 e8 91 46 cc f7 fb bf 01 00 00 00 76 d4 9f f7 65 8b 05 17 d4 50 76 85 c0 74 02 5b c3 e8 c4 de 4e
RSP: 0018:ffffc9000326fbc0 EFLAGS: 00000282
RAX: 55aac541ec95fe00 RBX: ffff888018d90940 RCX: 55aac541ec95fe00
RDX: dffffc0000000000 RSI: ffffffff8a0b15c0 RDI: 0000000000000001
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed10031b2129
R10: ffffed10031b2129 R11: 1ffff110031b2128 R12: ffff888018d90940
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000004000000
spin_unlock_irq include/linux/spinlock.h:413 [inline]
get_signal+0x11d6/0x12c0 kernel/signal.c:2903
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
sched: RT throttling activated
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f26388cc29b
Code: fe ff ff eb 23 66 2e 0f 1f 84 00 00 00 00 00 45 31 c0 31 c9 ba 80 00 00 00 48 89 de bf ca 00 00 00 31 c0 e8 67 fa 12 00 8b 03 <85> c0 74 e1 c7 45 08 00 00 00 00 45 84 ed 74 2d 80 3d 32 f4 e4 00
RSP: 002b:00007f2637c740f0 EFLAGS: 00000286
RAX: 0000000000000000 RBX: 00007f2638bebfa8 RCX: ffffffffffffffa8
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2638bebfa8
RBP: 00007f2638bebfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2638bebfac
R13: 0000000000000000 R14: 00007ffd971908d0 R15: 00007ffd971909b8