The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From ee050a577523dfd5fac95e6cc182ebe0293ead59 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Wed, 21 Apr 2021 19:21:24 -0700
Subject: [PATCH] KVM: nVMX: Truncate bits 63:32 of VMCS field on nested check
in !64-bit
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@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210422022128.3464144-6-seanjc@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 0f8c118ebc35..f93ff2302b4c 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -5745,7 +5745,7 @@ 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)
