rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P30/2:b..l P29576/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=165877, q=506 ncpus=2)
task:syz.6.7845 state:R running task stack:25880 pid:29576 tgid:29575 ppid:27957 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7190
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x479/0x23d0 arch/x86/kernel/unwind_orc.c:520
Code: 03 5b 00 48 c7 c1 40 c3 41 8d 31 d2 84 c0 48 0f 45 d1 48 89 15 e8 60 45 10 48 85 d2 0f 84 40 02 00 00 4c 8d 62 04 4c 8d 6a 05 <4c> 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6d 18 00 00 4c 89 e8
RSP: 0018:ffffc90005e6ed98 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffffffff8ef9bba4 RCX: ffffffff8ef9bba8
RDX: ffffffff8f73a018 RSI: ffffffff8f73a018 RDI: ffffffff8b3f5780
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8d5ae940
R10: ffffc90005e6eeb8 R11: ffffffff81ab9860 R12: ffffffff8f73a01c
R13: ffffffff8f73a01d R14: ffffc90005e6ee68 R15: ffffffff8ef9bba4
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:165
__set_page_owner+0x8d/0x4b0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857
prep_new_page mm/page_alloc.c:1865 [inline]
get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x39/0xe0 mm/mempolicy.c:2505
shmem_alloc_folio mm/shmem.c:1890 [inline]
shmem_alloc_and_add_folio mm/shmem.c:1932 [inline]
shmem_get_folio_gfp+0x633/0x1a70 mm/shmem.c:2556
shmem_fault+0x170/0x380 mm/shmem.c:2757
__do_fault+0x138/0x390 mm/memory.c:5320
do_shared_fault mm/memory.c:5819 [inline]
do_fault mm/memory.c:5893 [inline]
do_pte_missing+0x69d/0x27a0 mm/memory.c:4401
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault mm/memory.c:6411 [inline]
handle_mm_fault+0xcc1/0x1330 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x166e/0x2830 mm/gup.c:1428
__get_user_pages_locked mm/gup.c:1692 [inline]
faultin_page_range+0x240/0x8d0 mm/gup.c:1912
madvise_populate mm/madvise.c:976 [inline]
madvise_do_behavior+0x2e7/0x550 mm/madvise.c:1935
do_madvise+0x183/0x230 mm/madvise.c:2030
__do_sys_madvise mm/madvise.c:2039 [inline]
__se_sys_madvise mm/madvise.c:2037 [inline]
__x64_sys_madvise+0xa7/0xc0 mm/madvise.c:2037
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: 0033:0x7fe57335f749
RSP: 002b:00007fe5715be038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007fe5735b5fa0 RCX: 00007fe57335f749
RDX: 0000000000000017 RSI: 0000000000c00304 RDI: 0000200000000000
RBP: 00007fe5733e3f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe5735b6038 R14: 00007fe5735b5fa0 R15: 00007ffd65e75318
task:ksoftirqd/1 state:D stack:21624 pid:30 tgid:30 ppid:2 task_flags:0x4208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule_rtlock+0x30/0x70 kernel/sched/core.c:7024
rtlock_slowlock_locked+0x3819/0x4010 kernel/locking/rtmutex.c:1868
rtlock_slowlock kernel/locking/rtmutex.c:1895 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x158/0x3e0 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:44 [inline]
kcov_remote_stop+0xbe/0x690 kernel/kcov.c:1016
kcov_remote_stop_softirq include/linux/kcov.h:74 [inline]
__usb_hcd_giveback_urb+0x411/0x5e0 drivers/usb/core/hcd.c:1662
usb_giveback_urb_bh+0x296/0x420 drivers/usb/core/hcd.c:1695
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
bh_worker+0x2ca/0x630 kernel/workqueue.c:3611
tasklet_hi_action+0xf/0x70 kernel/softirq.c:958
handle_softirqs+0x1df/0x650 kernel/softirq.c:622
run_ksoftirqd+0x52/0x190 kernel/softirq.c:1063
smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10497 jiffies! g165877 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:27544 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
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:82
Code: c3 c2 03 00 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 43 c7 16 00 f3 0f 1e fa fb f4 98 c2 03 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8d207dc0 EFLAGS: 000002c6
RAX: 0000000001881167 RBX: ffffffff8195d78e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8ce0bc56 RDI: ffffffff8b3f57e0
RBP: ffffffff8d207eb0 R08: ffff8880b8833c5b R09: 1ffff1101710678b
R10: dffffc0000000000 R11: ffffed101710678c R12: ffffffff8edb3470
R13: 1ffffffff1a60668 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9780a4d876 CR3: 000000001bff4000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 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:757
start_kernel+0x381/0x3d0 init/main.c:1206
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