From mboxrd@z Thu Jan 1 00:00:00 1970 From: KarimAllah Ahmed Subject: [PATCH v6 01/14] X86/nVMX: handle_vmon: Read 4 bytes from guest memory Date: Thu, 31 Jan 2019 21:24:31 +0100 Message-ID: <1548966284-28642-2-git-send-email-karahmed@amazon.de> References: <1548966284-28642-1-git-send-email-karahmed@amazon.de> Cc: KarimAllah Ahmed To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Paolo Bonzini Return-path: In-Reply-To: <1548966284-28642-1-git-send-email-karahmed@amazon.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Read the data directly from guest memory instead of the map->read->unmap sequence. This also avoids using kvm_vcpu_gpa_to_page() and kmap() which assumes that there is a "struct page" for guest memory. Suggested-by: Jim Mattson Signed-off-by: KarimAllah Ahmed Reviewed-by: Jim Mattson Reviewed-by: David Hildenbrand Reviewed-by: Konrad Rzeszutek Wilk --- v1 -> v2: - Massage commit message a bit. --- arch/x86/kvm/vmx/nested.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 8ff2052..11b44a9 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4192,7 +4192,7 @@ static int handle_vmon(struct kvm_vcpu *vcpu) { int ret; gpa_t vmptr; - struct page *page; + uint32_t revision; struct vcpu_vmx *vmx = to_vmx(vcpu); const u64 VMXON_NEEDED_FEATURES = FEATURE_CONTROL_LOCKED | FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX; @@ -4241,18 +4241,10 @@ static int handle_vmon(struct kvm_vcpu *vcpu) if (!PAGE_ALIGNED(vmptr) || (vmptr >> cpuid_maxphyaddr(vcpu))) return nested_vmx_failInvalid(vcpu); - page = kvm_vcpu_gpa_to_page(vcpu, vmptr); - if (is_error_page(page)) + if (kvm_read_guest(vcpu->kvm, vmptr, &revision, sizeof(revision)) || + revision != VMCS12_REVISION) return nested_vmx_failInvalid(vcpu); - if (*(u32 *)kmap(page) != VMCS12_REVISION) { - kunmap(page); - kvm_release_page_clean(page); - return nested_vmx_failInvalid(vcpu); - } - kunmap(page); - kvm_release_page_clean(page); - vmx->nested.vmxon_ptr = vmptr; ret = enter_vmx_operation(vcpu); if (ret) -- 2.7.4