rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P13403/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=54325, q=670 ncpus=2)
task:syz.6.1825 state:R running task stack:25944 pid:13403 tgid:13402 ppid:11928 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:stack_access_ok+0x166/0x200 arch/x86/kernel/unwind_orc.c:398
Code: 0f 85 95 00 00 00 48 8b 43 10 49 39 ee 77 29 48 39 e8 76 24 4c 01 e5 48 39 e8 0f 93 c0 49 39 ee 0f 92 c2 21 d0 48 83 c4 08 5b <5d> 41 5c 41 5d 41 5e 41 5f e9 8c 6e 0e 0a 48 83 c4 08 31 c0 5b 5d
RSP: 0018:ffffc9000427ecc8 EFLAGS: 00000296
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffc90004280000
RDX: ffffc9000427f401 RSI: ffffc9000427f4c0 RDI: ffffc9000427ed68
RBP: ffffc9000427f4c0 R08: ffffffff912f7288 R09: 00000000f9f0d9a0
R10: 0000000000000002 R11: 0000000000012532 R12: 0000000000000008
R13: ffffc9000427ed78 R14: ffffc9000427ed70 R15: ffffc90004278000
deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
unwind_next_frame+0xb7d/0x20a0 arch/x86/kernel/unwind_orc.c:585
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:165
__set_page_owner+0x91/0x560 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846
prep_new_page mm/page_alloc.c:1854 [inline]
get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1890
shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1932
shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
shmem_fault+0x1fe/0xa00 mm/shmem.c:2757
__do_fault+0x10d/0x490 mm/memory.c:5320
do_read_fault mm/memory.c:5755 [inline]
do_fault+0xae4/0x1ad0 mm/memory.c:5889
do_pte_missing mm/memory.c:4401 [inline]
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x54e/0x3590 mm/gup.c:1428
populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860
__mm_populate+0x1d8/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3701 [inline]
vm_mmap_pgoff+0x37f/0x470 mm/util.c:586
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f73d6f8f749
RSP: 002b:00007f73d7df2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f73d71e5fa0 RCX: 00007f73d6f8f749
RDX: b635773f06ebbee2 RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f73d7013f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f73d71e6038 R14: 00007f73d71e5fa0 R15: 00007fffd0b69408
rcu: rcu_preempt kthread starved for 10454 jiffies! g54325 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28728 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
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+0x983/0xb10 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: c6 5f 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 13 59 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6
RAX: 0000000001c6badb RBX: 0000000000000001 RCX: ffffffff8b7806d9
RDX: 0000000000000000 RSI: ffffffff8dacdb2d RDI: ffffffff8bf2b300
RBP: ffffed1003bdb498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dedaff0 R12: 0000000000000001
R13: ffff88801deda4c0 R14: ffffffff9088aed0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881249f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc4446878c4 CR3: 00000000352af000 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:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148