Copy the VMCS12 directly from guest memory instead of the map->copy->unmap
sequence. This also avoids using kvm_vcpu_gpa_to_page() and kmap() which
assumes that there is a "struct page" for guest memory.

Signed-off-by: KarimAllah Ahmed <karah...@amazon.de>
---
v1 -> v2:
- Massage commit message a bit.
---
 arch/x86/kvm/vmx.c | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 358759a..bc45347 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8879,33 +8879,28 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
        }
 
        if (vmx->nested.current_vmptr != vmptr) {
-               struct vmcs12 *new_vmcs12;
-               struct page *page;
-               page = kvm_vcpu_gpa_to_page(vcpu, vmptr);
-               if (is_error_page(page)) {
+               struct vmcs12 *new_vmcs12 = (struct vmcs12 
*)__get_free_page(GFP_KERNEL);
+
+               if (!new_vmcs12 ||
+                   kvm_read_guest(vcpu->kvm, vmptr, new_vmcs12,
+                                  sizeof(*new_vmcs12))) {
+                       free_page((unsigned long)new_vmcs12);
                        nested_vmx_failInvalid(vcpu);
                        return kvm_skip_emulated_instruction(vcpu);
                }
-               new_vmcs12 = kmap(page);
+
                if (new_vmcs12->hdr.revision_id != VMCS12_REVISION ||
                    (new_vmcs12->hdr.shadow_vmcs &&
                     !nested_cpu_has_vmx_shadow_vmcs(vcpu))) {
-                       kunmap(page);
-                       kvm_release_page_clean(page);
+                       free_page((unsigned long)new_vmcs12);
                        nested_vmx_failValid(vcpu,
                                VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
                        return kvm_skip_emulated_instruction(vcpu);
                }
 
                nested_release_vmcs12(vmx);
-               /*
-                * Load VMCS12 from guest memory since it is not already
-                * cached.
-                */
                memcpy(vmx->nested.cached_vmcs12, new_vmcs12, VMCS12_SIZE);
-               kunmap(page);
-               kvm_release_page_clean(page);
-
+               free_page((unsigned long)new_vmcs12);
                set_current_vmptr(vmx, vmptr);
        }
 
-- 
2.7.4

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