rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15389/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=54449, q=217 ncpus=2)
task:syz-executor state:R running task stack:22424 pid:15389 tgid:15389 ppid:15372 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7238
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 d5 88 83 09 f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 41 66 ae 10 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 2e 55 cd
RSP: 0018:ffffc900057f71d8 EFLAGS: 00000286
RAX: 0636a2a4aeb4ea00 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 000000005158a735 RSI: ffffffff8d7c0ea8 RDI: ffffffff8ba67680
RBP: 0000000000000000 R08: ffffffff81767e65 R09: ffffffff8ddcb9c0
R10: ffffc900057f7338 R11: ffffffff81af9290 R12: 0000000000000002
R13: ffffffff8ddcb9c0 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x124/0x230 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
free_unref_folios+0xe7b/0x1c70 mm/page_alloc.c:3040
folios_put_refs+0x56f/0x680 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
shmem_truncate_range mm/shmem.c:1277 [inline]
shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407
evict+0x61e/0xb10 fs/inode.c:846
filename_unlinkat+0x445/0x610 fs/namei.c:5550
__do_sys_unlink fs/namei.c:5581 [inline]
__se_sys_unlink+0x2e/0x140 fs/namei.c:5578
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3027cdb907
RSP: 002b:00007fffa2b5c478 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3027cdb907
RDX: 00007fffa2b5c4a0 RSI: 00007fffa2b5c530 RDI: 00007fffa2b5c530
RBP: 00007fffa2b5c530 R08: 00007fffa2b5d530 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fffa2b5d5c0
R13: 00007f3027d72048 R14: 000000000015a2de R15: 00007fffa2b5d600
rcu: rcu_preempt kthread timer wakeup didn't happen for 10486 jiffies! g54449 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=49515
rcu: rcu_preempt kthread starved for 10487 jiffies! g54449 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27680 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16416 Comm: syz.6.2841 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:63
Code: 77 a6 8b e8 02 86 03 f6 e8 ed cb 0e f6 eb aa 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 89 fe 48 c7 c7 80 76 a6 8b e9 fd fe ff ff cc cc cc
RSP: 0018:ffffc90005707028 EFLAGS: 00000046
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 0000000000000002 RSI: ffff88803a961b70 RDI: ffffffff8d7c0ea8
RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90005707150 R11: fffff52000ae0e2d R12: 0000000000000246
R13: ffff88802e4cbd00 R14: ffff88803a961b70 R15: 0000000000000003
FS: 00007f8e995a66c0(0000) GS:ffff888126436000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000003a07c000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_is_held_type+0xdf/0x150 kernel/locking/lockdep.c:5941
lock_is_held include/linux/lockdep.h:249 [inline]
xa_head include/linux/xarray.h:1210 [inline]
xas_start+0x1eb/0x780 lib/xarray.c:191
xas_load+0x2c/0x5b0 lib/xarray.c:239
xa_load+0x118/0x210 lib/xarray.c:1619
kvm_get_memory_attributes include/linux/kvm_host.h:2519 [inline]
kvm_mem_is_private include/linux/kvm_host.h:2531 [inline]
kvm_mmu_faultin_pfn+0x2a5/0x15e0 arch/x86/kvm/mmu/mmu.c:4665
kvm_tdp_mmu_page_fault arch/x86/kvm/mmu/mmu.c:4904 [inline]
kvm_tdp_page_fault+0x273/0x370 arch/x86/kvm/mmu/mmu.c:4927
kvm_mmu_do_page_fault+0x33d/0x690 arch/x86/kvm/mmu/mmu_internal.h:381
kvm_mmu_page_fault+0x22d/0xb90 arch/x86/kvm/mmu/mmu.c:6434
__vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6929 [inline]
vmx_handle_exit+0xfd1/0x16c0 arch/x86/kvm/vmx/vmx.c:6939
vcpu_enter_guest arch/x86/kvm/x86.c:11520 [inline]
vcpu_run+0x5fa2/0x7b90 arch/x86/kvm/x86.c:11677
kvm_arch_vcpu_ioctl_run+0x11e6/0x20d0 arch/x86/kvm/x86.c:12025
kvm_vcpu_ioctl+0xa65/0xfe0 virt/kvm/kvm_main.c:4476
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e9b34c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8e995a6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8e9b5c5fa0 RCX: 00007f8e9b34c819
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007f8e9b3e2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8e9b5c6038 R14: 00007f8e9b5c5fa0 R15: 00007ffed701ba78