After reset, the CPU can change the BSP, which will be used upon INIT. Reset
should return the BSP which QEMU asked for, and therefore handled accordingly.
To quote: "If the MP protocol has completed and a BSP is chosen, subsequent
INITs (either to a specific processor or system wide) do not cause the MP
protocol to be repeated."
[Intel SDM 8.4.2: MP Initialization Protocol Requirements and Restrictions]
Signed-off-by: Nadav Amit <namit@xxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/lapic.c | 2 --
arch/x86/kvm/svm.c | 2 +-
arch/x86/kvm/vmx.c | 2 +-
include/linux/kvm_host.h | 7 ++++++-
4 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 17da6fc..b0dbf68 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1498,8 +1498,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
return;
}
- if (!kvm_vcpu_is_bsp(apic->vcpu))
- value &= ~MSR_IA32_APICBASE_BSP;
vcpu->arch.apic_base = value;
/* update jump label if enable bit changes */
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 1ef4c0d..ef5bf21 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1261,7 +1261,7 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
svm->vcpu.arch.apic_base = APIC_DEFAULT_PHYS_BASE |
MSR_IA32_APICBASE_ENABLE;
- if (kvm_vcpu_is_bsp(&svm->vcpu))
+ if (kvm_vcpu_is_reset_bsp(&svm->vcpu))
svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
svm_init_osvw(&svm->vcpu);
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8aee6db..7e370b2 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4709,7 +4709,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
if (!init_event) {
apic_base_msr.data = APIC_DEFAULT_PHYS_BASE |
MSR_IA32_APICBASE_ENABLE;
- if (kvm_vcpu_is_bsp(&vmx->vcpu))
+ if (kvm_vcpu_is_reset_bsp(&vmx->vcpu))
apic_base_msr.data |= MSR_IA32_APICBASE_BSP;
apic_base_msr.host_initiated = true;
kvm_set_apic_base(&vmx->vcpu, &apic_base_msr);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 0f574eb..8365cae 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -968,11 +968,16 @@ static inline int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
#endif /* CONFIG_HAVE_KVM_EVENTFD */
#ifdef CONFIG_KVM_APIC_ARCHITECTURE
-static inline bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
+static inline bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
{
return vcpu->kvm->bsp_vcpu_id == vcpu->vcpu_id;
}
+static inline bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
+{
+ return (vcpu->arch.apic_base & MSR_IA32_APICBASE_BSP) != 0;
+}
+
bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu);
#else
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
