[PATCH 5.4 145/178] KVM: X86: Fix MSR range of APIC registers in X2APIC mode

From: Sasha Levin
Date: Mon Jun 29 2020 - 15:54:32 EST


From: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>

commit bf10bd0be53282183f374af23577b18b5fbf7801 upstream.

Only MSR address range 0x800 through 0x8ff is architecturally reserved
and dedicated for accessing APIC registers in x2APIC mode.

Fixes: 0105d1a52640 ("KVM: x2apic interface to lapic")
Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
Message-Id: <20200616073307.16440-1-xiaoyao.li@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/x86.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fff279fb173bc..eed1866ae4d3a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2753,7 +2753,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return kvm_mtrr_set_msr(vcpu, msr, data);
case MSR_IA32_APICBASE:
return kvm_set_apic_base(vcpu, msr_info);
- case APIC_BASE_MSR ... APIC_BASE_MSR + 0x3ff:
+ case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
return kvm_x2apic_msr_write(vcpu, msr, data);
case MSR_IA32_TSCDEADLINE:
kvm_set_lapic_tscdeadline_msr(vcpu, data);
@@ -3057,7 +3057,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
case MSR_IA32_APICBASE:
msr_info->data = kvm_get_apic_base(vcpu);
break;
- case APIC_BASE_MSR ... APIC_BASE_MSR + 0x3ff:
+ case APIC_BASE_MSR ... APIC_BASE_MSR + 0xff:
return kvm_x2apic_msr_read(vcpu, msr_info->index, &msr_info->data);
break;
case MSR_IA32_TSCDEADLINE:
--
2.25.1