[PATCH] KVM: PPC: Don't always report hash MMU capability for P9 < DD2.2

[Fabiano Rosas]

These machines don't support running both MMU types at the same time,
so remove the KVM_CAP_PPC_MMU_HASH_V3 capability when the host is
using Radix MMU.

Signed-off-by: Fabiano Rosas <farosas at linux.ibm.com>
---
 arch/powerpc/include/asm/kvm_ppc.h |  1 +
 arch/powerpc/kvm/book3s_hv.c       | 10 ++++++++++
 arch/powerpc/kvm/powerpc.c         |  3 +--
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 0a056c64c317..b36abc89baf3 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -314,6 +314,7 @@ struct kvmppc_ops {
 			      int size);
 	int (*enable_svm)(struct kvm *kvm);
 	int (*svm_off)(struct kvm *kvm);
+	bool (*hash_v3_possible)(void);
 };
 
 extern struct kvmppc_ops *kvmppc_hv_ops;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 6f612d240392..d20c0682cae5 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -5599,6 +5599,15 @@ static int kvmhv_svm_off(struct kvm *kvm)
 	return ret;
 }
 
+static bool kvmppc_hash_v3_possible(void)
+{
+	if (radix_enabled() && no_mixing_hpt_and_radix)
+		return false;
+
+	return cpu_has_feature(CPU_FTR_ARCH_300) &&
+		cpu_has_feature(CPU_FTR_HVMODE);
+}
+
 static struct kvmppc_ops kvm_ops_hv = {
 	.get_sregs = kvm_arch_vcpu_ioctl_get_sregs_hv,
 	.set_sregs = kvm_arch_vcpu_ioctl_set_sregs_hv,
@@ -5642,6 +5651,7 @@ static struct kvmppc_ops kvm_ops_hv = {
 	.store_to_eaddr = kvmhv_store_to_eaddr,
 	.enable_svm = kvmhv_enable_svm,
 	.svm_off = kvmhv_svm_off,
+	.hash_v3_possible = kvmppc_hash_v3_possible,
 };
 
 static int kvm_init_subcore_bitmap(void)
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index cf52d26f49cd..b9fb2f20f879 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -611,8 +611,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		r = !!(hv_enabled && radix_enabled());
 		break;
 	case KVM_CAP_PPC_MMU_HASH_V3:
-		r = !!(hv_enabled && cpu_has_feature(CPU_FTR_ARCH_300) &&
-		       cpu_has_feature(CPU_FTR_HVMODE));
+		r = !!(hv_enabled && kvmppc_hv_ops->hash_v3_possible());
 		break;
 	case KVM_CAP_PPC_NESTED_HV:
 		r = !!(hv_enabled && kvmppc_hv_ops->enable_nested &&
-- 
2.29.2