rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15458/3:b..l P15423/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=63005, q=41 ncpus=2)
task:syz.2.2312 state:R running task stack:26904 pid:15423 tgid:15419 ppid:5823 task_flags:0x40044c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
irqentry_exit+0x36/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: a6 08 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 33 e9 0e 0f 82 74 02 00 00 8b 35 9a 63 e9 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 39 a6 08 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900052a6dd0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c4720 RCX: 000000009c6af5eb
RDX: 0000000000000000 RSI: ffffffff8da05cdf RDI: ffffffff8bf070c0
RBP: 0000000000000002 R08: 04c458fa08cd7175 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:311
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
free_unref_folios+0xa31/0x1610 mm/page_alloc.c:2963
folios_put_refs+0x4be/0x750 mm/swap.c:1002
free_pages_and_swap_cache+0x245/0x4a0 mm/swap_state.c:355
__tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0xe9/0x5a0 mm/mmu_gather.c:404
zap_pte_range mm/memory.c:1893 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x1f1e/0x41b0 mm/memory.c:2017
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:2060
unmap_vmas+0x218/0x470 mm/memory.c:2104
exit_mmap+0x1b2/0xb90 mm/mmap.c:1280
__mmput+0x12a/0x410 kernel/fork.c:1133
mmput+0x62/0x70 kernel/fork.c:1156
exit_mm kernel/exit.c:582 [inline]
do_exit+0x7c7/0x2bf0 kernel/exit.c:954
do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x426/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc4d678f6c9
RSP: 002b:00007fc4d7630038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007fc4d69e6090 RCX: 00007fc4d678f6c9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fc4d6811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc4d69e6128 R14: 00007fc4d69e6090 R15: 00007ffec6c9f2b8
task:dhcpcd-run-hook state:R running task stack:25864 pid:15458 tgid:15458 ppid:5480 task_flags:0x400000 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7113
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
filemap_map_pages+0xcbe/0x1b70 mm/filemap.c:3858
do_fault_around mm/memory.c:5656 [inline]
do_read_fault mm/memory.c:5689 [inline]
do_fault mm/memory.c:5832 [inline]
do_pte_missing+0xe33/0x3ba0 mm/memory.c:4361
handle_pte_fault mm/memory.c:6177 [inline]
__handle_mm_fault+0x1556/0x2aa0 mm/memory.c:6318
handle_mm_fault+0x589/0xd10 mm/memory.c:6487
do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fdf9cb51000
RSP: 002b:00007ffcc7e08c68 EFLAGS: 00010206
RAX: 00007fdf9cb51000 RBX: 00007fdf9cbba6b0 RCX: 00007ffcc7e08d00
RDX: 00007ffcc7e08d00 RSI: 00007ffcc7e08ce8 RDI: 0000000000000002
RBP: 0000000000000002 R08: 00007fdf9cef4af8 R09: 0000000000000000
R10: 00007ffcc7e08910 R11: 0000000000000246 R12: 00007ffcc7e08ce8
R13: 00007ffcc7e08d00 R14: 00007fdf9cef7310 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10573 jiffies! g63005 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:28392 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 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 10/02/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: d7 6c 02 c3 cc cc cc cc 0f 1f 00 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 23 86 29 00 fb f4 3c 0a 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 0000000004cea0c1 RBX: 0000000000000000 RCX: ffffffff8b60a2a9
RDX: 0000000000000000 RSI: ffffffff8da2b6a1 RDI: ffffffff8bf070c0
RBP: fffffbfff1c12f40 R08: 0000000000000001 R09: ffffed1017086655
R10: ffff8880b84332ab R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff8e097a00 R14: ffffffff90820cd0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124a08000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf9cb51000 CR3: 000000005ba71000 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+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x38d/0x500 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3f6/0x4e0 init/main.c:1111
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148