[PATCH v2 2/6] KVM: x86/mmu: Fix wrong gfn range of tlb flushing in kvm_set_pte_rmapp()

Hou Wenlong
2022-08-24T09:29:50Z

When the spte of hupe page is dropped in kvm_set_pte_rmapp(),
the whole gfn range covered by the spte should be flushed.
However, rmap_walk_init_level() doesn't align down the gfn
for new level like tdp iterator does, then the gfn used in
kvm_set_pte_rmapp() is not the base gfn of huge page. And
the size of gfn range is wrong too for huge page. Use the
base gfn of huge page and the size of huge page for
flushing tlbs for huge page.

Fixes: c3134ce240eed ("KVM: Replace old tlb flush function with new one to flush a specified range.")
Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
---
arch/x86/kvm/mmu/mmu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a3578abd8bbc..3bcff56df109 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1438,7 +1438,8 @@ static bool kvm_set_pte_rmap(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
}

if (need_flush && kvm_available_flush_tlb_with_range()) {
- kvm_flush_remote_tlbs_with_address(kvm, gfn, 1);
+ kvm_flush_remote_tlbs_with_address(kvm, gfn & -KVM_PAGES_PER_HPAGE(level),
+ KVM_PAGES_PER_HPAGE(level));
return false;
}

--
2.31.1