rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=fd64/1/0x4000000000000000 softirq=78378/78378 fqs=995
rcu: (detected by 0, t=10502 jiffies, g=70393, q=249 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14728 Comm: syz.5.2149 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1783 [inline]
RIP: 0010:__hrtimer_run_queues+0x495/0xc30 kernel/time/hrtimer.c:1849
Code: 45 84 ff 74 14 e8 cb 9b f8 ff 84 c0 0f 84 94 02 00 00 e8 be 87 12 00 eb 05 e8 b7 87 12 00 4d 8d 6c 24 3b 4c 89 e8 48 c1 e8 03 <48> b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 21 03 00 00
RSP: 0018:ffffc90000a08d40 EFLAGS: 00000802
RAX: 1ffff1100e760267 RBX: ffff8880b87283c8 RCX: ffff888025f43c80
RDX: 0000000000010000 RSI: ffffffff8be09740 RDI: ffffffff8be09700
RBP: ffffc90000a08e90 R08: ffffffff8fa2d9f7 R09: 1ffffffff1f45b3e
R10: dffffc0000000000 R11: fffffbfff1f45b3f R12: ffff888073b01300
R13: ffff888073b0133b R14: ffffffff89752fc0 R15: 0000000000000001
FS: 00007f917a3916c0(0000) GS:ffff888125cf9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3e1d58 CR3: 0000000084096000 CR4: 00000000003526f0
Call Trace:
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1911
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194
Code: f7 e8 8d cb 3d f6 f7 c3 00 02 00 00 74 05 e8 30 a9 67 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 d4 d6 2f f6 65 8b 05 1d 39 41 07 85 c0 74 18 5b 41 5e e9 01 47
RSP: 0018:ffffc9000dc1faa8 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000246 RCX: 0000000080000001
RDX: 0000000000000007 RSI: ffffffff8d9a73db RDI: 0000000000000001
RBP: ffffc9000dc1fbd0 R08: ffffffff8fa2d9f7 R09: 1ffffffff1f45b3e
R10: dffffc0000000000 R11: fffffbfff1f45b3f R12: 0000000000000000
R13: ffff8880b8628280 R14: ffff8880b8628280 R15: dffffc0000000000
clock_was_set+0x63b/0x7c0 kernel/time/hrtimer.c:973
do_adjtimex+0x228/0x310 kernel/time/timekeeping.c:2767
do_clock_adjtime kernel/time/posix-timers.c:1154 [inline]
__do_sys_clock_adjtime kernel/time/posix-timers.c:1166 [inline]
__se_sys_clock_adjtime kernel/time/posix-timers.c:1157 [inline]
__x64_sys_clock_adjtime+0x211/0x2c0 kernel/time/posix-timers.c:1157
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f917958f749
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:00007f917a391038 EFLAGS: 00000246 ORIG_RAX: 0000000000000131
RAX: ffffffffffffffda RBX: 00007f91797e5fa0 RCX: 00007f917958f749
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000000
RBP: 00007f9179613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f91797e6038 R14: 00007f91797e5fa0 R15: 00007ffef75cfd88
rcu: rcu_preempt kthread starved for 5525 jiffies! g70393 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:27576 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5290 [inline]
__schedule+0x14db/0x5030 kernel/sched/core.c:6902
__schedule_loop kernel/sched/core.c:6984 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6999
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:63
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 bd 29 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 00000246
RAX: 00000000017ae20f RBX: ffffffff8197831e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a73db RDI: ffffffff8be09760
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa2d9f0
R13: 1ffffffff1bd29d0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125bf9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff472abbb89 CR3: 000000002e6b8000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:760
start_kernel+0x386/0x3d0 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147