rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P37/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=73789, q=512 ncpus=2)
task:khugepaged state:R running task stack:26872 pid:37 tgid:37 ppid:2 task_flags:0x200040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7413
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
__collapse_huge_page_copy_succeeded mm/khugepaged.c:879 [inline]
__collapse_huge_page_copy mm/khugepaged.c:963 [inline]
collapse_huge_page+0x23dc/0x3c60 mm/khugepaged.c:1412
mthp_collapse mm/khugepaged.c:1523 [inline]
collapse_scan_pmd mm/khugepaged.c:1785 [inline]
collapse_single_pmd+0x313c/0x45a0 mm/khugepaged.c:2798
collapse_scan_mm_slot mm/khugepaged.c:2913 [inline]
khugepaged_do_scan mm/khugepaged.c:2993 [inline]
khugepaged+0x10e6/0x14e0 mm/khugepaged.c:3048
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread timer wakeup didn't happen for 10497 jiffies! g73789 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=38311
rcu: rcu_preempt kthread starved for 10498 jiffies! g73789 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27592 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15497 Comm: syz.3.2607 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:23 [inline]
RIP: 0010:lock_acquire+0x4a/0x370 kernel/locking/lockdep.c:5831
Code: 65 4c 8b 3d 20 df 7d 12 4c 89 7c 24 30 4d 89 cf 66 90 65 8b 05 3b df 7d 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 86 c4 3c 0f <0f> 82 ac 02 00 00 8b 35 4e f8 3c 0f 85 f6 0f 85 c7 00 00 00 48 8b
RSP: 0018:ffffc90000a08e10 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880b8528418
RBP: ffff8880b8528418 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f01e124c6c0(0000) GS:ffff888123eec000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2647d1 CR3: 000000002ddd5000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:174
__run_hrtimer kernel/time/hrtimer.c:2036 [inline]
__hrtimer_run_queues+0x1b7/0x9c0 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 16 bf 29 f6 48 89 df e8 9e 0e 2a f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 95 1f 19 f6 65 8b 05 ee 98 a7 08 85 c0 74 16 5b
RSP: 0018:ffffc90006eb7d78 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff9b72f3d8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8e1a29fc RDI: ffffffff8c400c80
RBP: 0000000000000283 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffffffffffff R12: 1ffff92000dd6fb6
R13: 000000000cec3f94 R14: 000000000cec3f94 R15: 0000000000000000
class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:571 [inline]
do_settimeofday64+0x326/0x4d0 kernel/time/timekeeping.c:1665
do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:195
__do_sys_clock_settime kernel/time/posix-timers.c:1139 [inline]
__se_sys_clock_settime kernel/time/posix-timers.c:1123 [inline]
__x64_sys_clock_settime+0x1c1/0x2a0 kernel/time/posix-timers.c:1123
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f01e039de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f01e124c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f01e0626090 RCX: 00007f01e039de59
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007f01e0433e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f01e0626128 R14: 00007f01e0626090 R15: 00007ffd2ed22628