rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17364/1:b..l P22410/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=132289, q=13608 ncpus=2)
task:syz.3.4282 state:R running task stack:26312 pid:22410 tgid:22409 ppid:19795 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_irq+0xb5/0x150 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:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 d4 38 e0 10 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90010476f98 EFLAGS: 00000206
RAX: 2216dc09d9a87c00 RBX: 0000000000000000 RCX: 2216dc09d9a87c00
RDX: 00000000811e2f62 RSI: ffffffff8d979233 RDI: ffffffff8bc08360
RBP: ffffffff82339b8a R08: ffffffff82339b8a R09: ffffffff8df41a20
R10: dffffc0000000000 R11: ffffed100fa475d0 R12: 0000000000000002
R13: ffffffff8df41a20 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
__page_table_check_zero+0x87/0x3e0 mm/page_table_check.c:138
page_table_check_alloc include/linux/page_table_check.h:35 [inline]
post_alloc_hook+0x247/0x290 mm/page_alloc.c:1847
prep_new_page mm/page_alloc.c:1854 [inline]
get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505
shmem_alloc_folio mm/shmem.c:1890 [inline]
shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1932
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2556
shmem_fault+0x179/0x390 mm/shmem.c:2757
__do_fault+0x138/0x390 mm/memory.c:5320
do_read_fault mm/memory.c:5755 [inline]
do_fault mm/memory.c:5889 [inline]
do_pte_missing+0x2206/0x3330 mm/memory.c:4401
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault mm/memory.c:6411 [inline]
handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x1650/0x29f0 mm/gup.c:1428
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860
__mm_populate+0x24c/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3701 [inline]
vm_mmap_pgoff+0x387/0x4d0 mm/util.c:586
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f74b8f749
RSP: 002b:00007f6f75aa6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f6f74de5fa0 RCX: 00007f6f74b8f749
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f6f74c13f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6f74de6038 R14: 00007f6f74de5fa0 R15: 00007fffb6c9d1c8
task:syz-executor state:R running task stack:20944 pid:17364 tgid:17364 ppid:17351 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071
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+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1331 [inline]
copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1581
copy_process+0x165d/0x3950 kernel/fork.c:2221
kernel_clone+0x21e/0x820 kernel/fork.c:2651
__do_sys_clone kernel/fork.c:2792 [inline]
__se_sys_clone kernel/fork.c:2776 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb387f85e93
RSP: 002b:00007ffee13fef68 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb387f85e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055558823f7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000001a04b2 R15: 00007ffee13ff100
rcu: rcu_preempt kthread starved for 10585 jiffies! g132289 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:27152 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 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+0x599/0xb30 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(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: 5e 83 b4 f5 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 93 90 0c 00 f3 0f 1e fa fb f4 33 83 b4 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 2be925207e4bc400 RBX: ffffffff81978fda RCX: 2be925207e4bc400
RDX: 0000000000000001 RSI: ffffffff8d7925c0 RDI: ffffffff8bc08360
RBP: ffffffff8dc07ea8 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f822070
R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f00173b8440 CR3: 000000007d24e000 CR4: 0000000000350ef0
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+0x1ea/0x520 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+0x3a7/0x400 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