Re: [PATCH v5 12/13] KVM/nVMX: Use kvm_vcpu_map for accessing the enlightened VMCS

[Konrad Rzeszutek Wilk]

On Wed, Jan 09, 2019 at 10:42:12AM +0100, KarimAllah Ahmed wrote:
> Use kvm_vcpu_map for accessing the enhanced VMCS since using
> kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
> a "struct page".
> 
> Signed-off-by: KarimAllah Ahmed 

Reviewed-by: Konrad Rzeszutek Wilk 

[PATCH v5 12/13] KVM/nVMX: Use kvm_vcpu_map for accessing the enlightened VMCS

[KarimAllah Ahmed]

Use kvm_vcpu_map for accessing the enhanced VMCS since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".

Signed-off-by: KarimAllah Ahmed 

---
v4 -> v5:
- s/enhanced/enlightened
- unmap with dirty flag
---
 arch/x86/kvm/vmx/nested.c | 14 +-
 arch/x86/kvm/vmx/vmx.h|  2 +-
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 04a8b43..ccb3b63 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -193,10 +193,8 @@ static inline void nested_release_evmcs(struct kvm_vcpu 
*vcpu)
if (!vmx->nested.hv_evmcs)
return;
 
-   kunmap(vmx->nested.hv_evmcs_page);
-   kvm_release_page_dirty(vmx->nested.hv_evmcs_page);
+   kvm_vcpu_unmap(&vmx->nested.hv_evmcs_map, true);
vmx->nested.hv_evmcs_vmptr = -1ull;
-   vmx->nested.hv_evmcs_page = NULL;
vmx->nested.hv_evmcs = NULL;
 }
 
@@ -1769,13 +1767,11 @@ static int nested_vmx_handle_enlightened_vmptrld(struct 
kvm_vcpu *vcpu,
 
nested_release_evmcs(vcpu);
 
-   vmx->nested.hv_evmcs_page = kvm_vcpu_gpa_to_page(
-   vcpu, assist_page.current_nested_vmcs);
-
-   if (unlikely(is_error_page(vmx->nested.hv_evmcs_page)))
+   if (kvm_vcpu_map(vcpu, 
gpa_to_gfn(assist_page.current_nested_vmcs),
+&vmx->nested.hv_evmcs_map))
return 0;
 
-   vmx->nested.hv_evmcs = kmap(vmx->nested.hv_evmcs_page);
+   vmx->nested.hv_evmcs = vmx->nested.hv_evmcs_map.hva;
 
/*
 * Currently, KVM only supports eVMCS version 1
@@ -4278,7 +4274,7 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
return nested_vmx_failValid(vcpu,
VMXERR_VMCLEAR_VMXON_POINTER);
 
-   if (vmx->nested.hv_evmcs_page) {
+   if (vmx->nested.hv_evmcs_map.hva) {
if (vmptr == vmx->nested.hv_evmcs_vmptr)
nested_release_evmcs(vcpu);
} else {
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index bd04725..a130139 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -172,7 +172,7 @@ struct nested_vmx {
} smm;
 
gpa_t hv_evmcs_vmptr;
-   struct page *hv_evmcs_page;
+   struct kvm_host_map hv_evmcs_map;
struct hv_enlightened_vmcs *hv_evmcs;
 };
 
-- 
2.7.4