[PATCH v11 07/35] KVM: x86: Add KVM_X86_SNP_VM vm_type

From: Michael Roth
Date: Sat Dec 30 2023 - 12:37:52 EST


In some cases, such as detecting whether a page fault should be handled
as a private fault or not, KVM will need to handle things differently
versus the existing KVM_X86_PROTECTED_VM type.

Add a new KVM_X86_SNP_VM to allow for this, along with a helper to query
the vm_type.

Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/include/uapi/asm/kvm.h | 1 +
arch/x86/kvm/x86.c | 20 +++++++++++++++++---
3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 63596fe45013..e38cab5dccae 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2141,6 +2141,8 @@ void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level,
#define kvm_arch_has_private_mem(kvm) false
#endif

+bool kvm_is_vm_type(struct kvm *kvm, unsigned long type);
+
static inline u16 kvm_read_ldt(void)
{
u16 ldt;
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index a448d0964fc0..57e4ba484aa2 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -564,5 +564,6 @@ struct kvm_pmu_event_filter {

#define KVM_X86_DEFAULT_VM 0
#define KVM_X86_SW_PROTECTED_VM 1
+#define KVM_X86_SNP_VM 3

#endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index aaf71e5c1d18..87b78d63e81d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4579,9 +4579,21 @@ static int kvm_ioctl_get_supported_hv_cpuid(struct kvm_vcpu *vcpu,

static bool kvm_is_vm_type_supported(unsigned long type)
{
- return type == KVM_X86_DEFAULT_VM ||
- (type == KVM_X86_SW_PROTECTED_VM &&
- IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled);
+ if (type == KVM_X86_DEFAULT_VM)
+ return true;
+ else if (type == KVM_X86_SW_PROTECTED_VM &&
+ IS_ENABLED(CONFIG_KVM_SW_PROTECTED_VM) && tdp_enabled)
+ return true;
+ else if (type == KVM_X86_SNP_VM &&
+ IS_ENABLED(CONFIG_KVM_AMD_SEV) && tdp_enabled)
+ return true;
+
+ return false;
+}
+
+bool kvm_is_vm_type(struct kvm *kvm, unsigned long type)
+{
+ return kvm->arch.vm_type == type;
}

int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
@@ -4784,6 +4796,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
r = BIT(KVM_X86_DEFAULT_VM);
if (kvm_is_vm_type_supported(KVM_X86_SW_PROTECTED_VM))
r |= BIT(KVM_X86_SW_PROTECTED_VM);
+ if (kvm_is_vm_type_supported(KVM_X86_SNP_VM))
+ r |= BIT(KVM_X86_SNP_VM);
break;
default:
break;
--
2.25.1