From: David Woodhouse <dwmw@xxxxxxxxxxxx>
commit 8332f0ed4f187c7b700831bd7cc83ce180a944b9 upstream.
In the case where a GPC is refreshed to a different location within the
same page, we didn't bother to update it. Mostly we don't need to, but
since the ->khva field also includes the offset within the page, that
does have to be updated.
Fixes: 3ba2c95ea180 ("KVM: Do not incorporate page offset into gfn=>pfn cache user address")
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Reviewed-by: Paul Durrant <paul@xxxxxxx>
Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Cc: stable@xxxxxxxxxx
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
virt/kvm/pfncache.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -297,7 +297,12 @@ int kvm_gfn_to_pfn_cache_refresh(struct
if (!gpc->valid || old_uhva != gpc->uhva) {
ret = hva_to_pfn_retry(kvm, gpc);
} else {
- /* If the HVA→PFN mapping was already valid, don't unmap it. */
+ /*
+ * If the HVA→PFN mapping was already valid, don't unmap it.
+ * But do update gpc->khva because the offset within the page
+ * may have changed.
+ */
+ gpc->khva = old_khva + page_offset;
old_pfn = KVM_PFN_ERR_FAULT;
old_khva = NULL;
ret = 0;
