[PATCH v2 3/7] KVM x86: Extend AMD specific guest behavior to Hygon virtual CPUs

Sean Christopherson
2020-03-05T01:34:49Z

Extend guest_cpuid_is_amd() to cover Hygon virtual CPUs and rename it
accordingly. Hygon CPUs use an AMD-based core and so have the same
basic behavior as AMD CPUs.

Fixes: b8f4abb652146 ("x86/kvm: Add Hygon Dhyana support to KVM")
Cc: Pu Wen <puwen@hygon.cn>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/cpuid.c | 2 +-
arch/x86/kvm/cpuid.h | 6 ++++--
arch/x86/kvm/mmu/mmu.c | 3 ++-
arch/x86/kvm/x86.c | 2 +-
4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b4beb3707d1b..5a9891cb2bc6 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -1013,7 +1013,7 @@ bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
* requested. AMD CPUID semantics returns all zeroes for any
* undefined leaf, whether or not the leaf is in range.
*/
- if (!entry && check_limit && !guest_cpuid_is_amd(vcpu) &&
+ if (!entry && check_limit && !guest_cpuid_is_amd_or_hygon(vcpu) &&
!cpuid_function_in_range(vcpu, function)) {
max = kvm_find_cpuid_entry(vcpu, 0, 0);
if (max) {
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 13eb3e92c6a9..332068db0fc2 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -140,12 +140,14 @@ static __always_inline void guest_cpuid_clear(struct kvm_vcpu *vcpu, unsigned x8
*reg &= ~__feature_bit(x86_feature);
}

-static inline bool guest_cpuid_is_amd(struct kvm_vcpu *vcpu)
+static inline bool guest_cpuid_is_amd_or_hygon(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;

best = kvm_find_cpuid_entry(vcpu, 0, 0);
- return best && is_guest_vendor_amd(best->ebx, best->ecx, best->edx);
+ return best &&
+ (is_guest_vendor_amd(best->ebx, best->ecx, best->edx) ||
+ is_guest_vendor_hygon(best->ebx, best->ecx, best->edx));
}

static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index a1f4e325420e..c7ef2745a4e0 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4507,7 +4507,8 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
cpuid_maxphyaddr(vcpu), context->root_level,
context->nx,
guest_cpuid_has(vcpu, X86_FEATURE_GBPAGES),
- is_pse(vcpu), guest_cpuid_is_amd(vcpu));
+ is_pse(vcpu),
+ guest_cpuid_is_amd_or_hygon(vcpu));
}

static void
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fa03f31ab33c..1a4836ed1230 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2524,7 +2524,7 @@ static void kvmclock_sync_fn(struct work_struct *work)
static bool can_set_mci_status(struct kvm_vcpu *vcpu)
{
/* McStatusWrEn enabled? */
- if (guest_cpuid_is_amd(vcpu))
+ if (guest_cpuid_is_amd_or_hygon(vcpu))
return !!(vcpu->arch.msr_hwcr & BIT_ULL(18));

return false;
--
2.24.1