From: Sean Christopherson <seanjc@google.com>
Date: Wed, 21 Apr 2021 19:21:24 -0700
Subject: KVM: nVMX: Truncate bits 63:32 of VMCS field on nested check in
!64-bit
Git-commit: ee050a577523dfd5fac95e6cc182ebe0293ead59
Patch-mainline: v5.13-rc1
References: bsc#1188784
Drop bits 63:32 of the VMCS field encoding when checking for a nested
VM-Exit on VMREAD/VMWRITE in !64-bit mode. VMREAD and VMWRITE always
use 32-bit operands outside of 64-bit mode.
The actual emulation of VMREAD/VMWRITE does the right thing, this bug is
purely limited to incorrectly causing a nested VM-Exit if a GPR happens
to have bits 63:32 set outside of 64-bit mode.
Fixes: a7cde481b6e8 ("KVM: nVMX: Do not forward VMREAD/VMWRITE VMExits to L1 if required so by vmcs12 vmread/vmwrite bitmaps")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210422022128.3464144-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jose R. Ziviani <jziviani@suse.de>
---
arch/x86/kvm/vmx/nested.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index a0b4b78409cc..14093234438f 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5330,7 +5330,7 @@ static bool nested_vmx_exit_handled_vmcs_access(struct kvm_vcpu *vcpu,
/* Decode instruction info and find the field to access */
vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO);
- field = kvm_register_read(vcpu, (((vmx_instruction_info) >> 28) & 0xf));
+ field = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 28) & 0xf));
/* Out-of-range fields always cause a VM exit from L2 to L1 */
if (field >> 15)
--
2.32.0