KVM: Update gfn_to_pfn_cache khva when it moves within the same page

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: 3ba2c95ea1 ("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>
This commit is contained in:
David Woodhouse 2022-11-19 09:25:39 +00:00 committed by Paolo Bonzini
parent c2b8cdfaf3
commit 8332f0ed4f

View File

@ -297,7 +297,12 @@ int kvm_gfn_to_pfn_cache_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc,
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 HVAPFN 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;