syzbot

raw: 01ffd20000000000 ffffc1ffc07b3d08 ffffc1ffc07b5a08 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0)
------------[ cut here ]------------
kernel BUG at ./include/linux/mm.h:1036!
Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
Modules linked in:
CPU: 0 UID: 0 PID: 3601 Comm: syz.0.41 Not tainted syzkaller #0 PREEMPT 
Hardware name: linux,dummy-virt (DT)
pstate: 61402009 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : put_page_testzero include/linux/mm.h:1036 [inline]
pc : folio_put_testzero include/linux/mm.h:1042 [inline]
pc : folio_put include/linux/mm.h:1359 [inline]
pc : put_page include/linux/mm.h:1429 [inline]
pc : kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264
lr : put_page_testzero include/linux/mm.h:1036 [inline]
lr : folio_put_testzero include/linux/mm.h:1042 [inline]
lr : folio_put include/linux/mm.h:1359 [inline]
lr : put_page include/linux/mm.h:1429 [inline]
lr : kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264
sp : ffff8000a3f97570
x29: ffff8000a3f97570 x28: 87f000001ed68000 x27: 87f000001ed68000
x26: 00000000000000ff x25: ffff80008734e000 x24: ffffc1ffc0000000
x23: ffffc1ffc0779a08 x22: 0000000000000000 x21: ffffc1ffc0779a34
x20: 0000000000000000 x19: ffffc1ffc0779a00 x18: 00000000458147dd
x17: 000000000278602a x16: 000000004508e096 x15: 000000003f044397
x14: ffffffffffffffff x13: fff000001e3e8008 x12: 0000000000000001
x11: 0000000000080000 x10: 000000000007ffff x9 : 34c5b7252f276f00
x8 : 34c5b7252f276f00 x7 : ffff8000803a03c8 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800080758a9c
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000003e
Call trace:
 put_page_testzero include/linux/mm.h:1036 [inline] (P)
 folio_put_testzero include/linux/mm.h:1042 [inline] (P)
 folio_put include/linux/mm.h:1359 [inline] (P)
 put_page include/linux/mm.h:1429 [inline] (P)
 kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264 (P)
 stage2_free_walker+0x1b0/0x264 arch/arm64/kvm/hyp/pgtable.c:1549
 kvm_pgtable_visitor_cb arch/arm64/kvm/hyp/pgtable.c:130 [inline]
 __kvm_pgtable_visit arch/arm64/kvm/hyp/pgtable.c:212 [inline]
 __kvm_pgtable_walk+0x7d8/0xa68 arch/arm64/kvm/hyp/pgtable.c:237
 _kvm_pgtable_walk arch/arm64/kvm/hyp/pgtable.c:260 [inline]
 kvm_pgtable_walk+0x294/0x468 arch/arm64/kvm/hyp/pgtable.c:283
 kvm_pgtable_stage2_destroy_range+0x60/0xb4 arch/arm64/kvm/hyp/pgtable.c:1563
 stage2_destroy_range arch/arm64/kvm/mmu.c:924 [inline]
 kvm_stage2_destroy arch/arm64/kvm/mmu.c:935 [inline]
 kvm_free_stage2_pgd+0x198/0x28c arch/arm64/kvm/mmu.c:1112
 kvm_uninit_stage2_mmu+0x20/0x38 arch/arm64/kvm/mmu.c:1023
 kvm_arch_flush_shadow_all+0x1a8/0x1e0 arch/arm64/kvm/nested.c:1113
 kvm_flush_shadow_all virt/kvm/kvm_main.c:343 [inline]
 kvm_mmu_notifier_release+0x48/0xa8 virt/kvm/kvm_main.c:884
 mmu_notifier_unregister+0x128/0x42c mm/mmu_notifier.c:815
 kvm_destroy_vm virt/kvm/kvm_main.c:1295 [inline]
 kvm_put_kvm+0x6a0/0xfa8 virt/kvm/kvm_main.c:1353
 kvm_vcpu_release+0x70/0x9c virt/kvm/kvm_main.c:4100
 __fput+0x4ac/0x980 fs/file_table.c:468
 ____fput+0x20/0x58 fs/file_table.c:496
 task_work_run+0x1bc/0x254 kernel/task_work.c:227
 get_signal+0x13ec/0x1554 kernel/signal.c:2807
 do_signal+0x23c/0x4dd0 arch/arm64/kernel/signal.c:1618
 do_notify_resume+0xb0/0x270 arch/arm64/kernel/entry-common.c:152
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline]
 el0_svc+0xb8/0x164 arch/arm64/kernel/entry-common.c:880
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
Code: f00375a1 91143421 aa1303e0 97f9c9f2 (d4210000) 
---[ end trace 0000000000000000 ]---