From: David Woodhouse dwmw@amazon.co.uk
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@amazon.co.uk Reviewed-by: Paul Durrant paul@xen.org Reviewed-by: Sean Christopherson seanjc@google.com Cc: stable@kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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;