rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12883/1:b..l P13623/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=51453, q=429 ncpus=2)
task:syz.7.1911 state:R running task stack:23536 pid:13623 tgid:13622 ppid:11261 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x643/0x2390 arch/x86/kernel/unwind_orc.c:515
Code: 28 00 74 08 48 89 df e8 4b 91 b0 00 48 8b 3b 48 85 ff 0f 84 5b 10 00 00 48 83 c7 10 e9 73 01 00 00 83 fb 04 0f 84 7b 01 00 00 <83> fb 05 0f 85 36 0c 00 00 48 8b 44 24 58 80 3c 28 00 74 11 4c 89
RSP: 0018:ffffc9001638ed38 EFLAGS: 00000202
RAX: ffffc9001638ee3d RBX: 0000000000000005 RCX: ffffffff8fdf1ddc
RDX: ffffffff905ed8ae RSI: ffffffff905ed8b2 RDI: ffffffff8c035820
RBP: dffffc0000000000 R08: 0000000000000004 R09: 0000000000000000
R10: ffffc9001638ee58 R11: ffffffff81ad2180 R12: ffffffff905ed8b3
R13: ffffc9001638ee58 R14: ffffc9001638ee08 R15: ffffc9001638ee40
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__set_page_owner+0x8d/0x4a0 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2435
shmem_alloc_folio mm/shmem.c:1908 [inline]
shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1947
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2597
shmem_fault+0x179/0x390 mm/shmem.c:2798
__do_fault+0x138/0x390 mm/memory.c:5280
do_read_fault mm/memory.c:5703 [inline]
do_fault mm/memory.c:5837 [inline]
do_pte_missing mm/memory.c:4362 [inline]
handle_pte_fault mm/memory.c:6182 [inline]
__handle_mm_fault+0x35e3/0x5400 mm/memory.c:6323
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492
faultin_page mm/gup.c:1144 [inline]
__get_user_pages+0x1699/0x2ce0 mm/gup.c:1446
populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1880
__mm_populate+0x24c/0x380 mm/gup.c:1983
mm_populate include/linux/mm.h:3423 [inline]
vm_mmap_pgoff+0x387/0x4d0 mm/util.c:585
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f874d78ebe9
RSP: 002b:00007f874e54a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f874d9b5fa0 RCX: 00007f874d78ebe9
RDX: b635773f06ebbeef RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f874d811e19 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f874d9b6038 R14: 00007f874d9b5fa0 R15: 00007ffc3cfb43d8
task:syz-executor state:R running task stack:21928 pid:12883 tgid:12883 ppid:12873 task_flags:0x400140 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
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:1329 [inline]
copy_pmd_range+0x7630/0x7f00 mm/memory.c:1389
copy_pud_range mm/memory.c:1426 [inline]
copy_p4d_range mm/memory.c:1450 [inline]
copy_page_range+0xc14/0x1270 mm/memory.c:1538
dup_mmap+0xf57/0x1ac0 mm/mmap.c:1834
dup_mm kernel/fork.c:1488 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1540
copy_process+0x1706/0x3c00 kernel/fork.c:2178
kernel_clone+0x21e/0x840 kernel/fork.c:2608
__do_sys_clone kernel/fork.c:2751 [inline]
__se_sys_clone kernel/fork.c:2735 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2735
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd2c2985453
RSP: 002b:00007ffeb3350268 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd2c2985453
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055557859a7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000812f6 R15: 00007ffeb3350400
rcu: rcu_preempt kthread starved for 8928 jiffies! g51453 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:27328 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
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+0x47c/0x820 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc 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 83 8f 29 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: 41f0b105f0a77300 RBX: ffffffff81976c78 RCX: 41f0b105f0a77300
RDX: 0000000000000001 RSI: ffffffff8c035860 RDI: ffffffff81976c78
RBP: ffffc90000197f10 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fc40330
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a55b40
FS: 0000000000000000(0000) GS:ffff888125aff000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd73bb3f6c8 CR3: 0000000028180000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147