3 files changed, 43 insertions, 2 deletions

diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
index 555cc610e7ab..912c1e9eef6b 100644
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -59,6 +59,25 @@
  */
 #define XIVE_Q_GAP	2
 
+static bool kvmppc_xive_vcpu_has_save_restore(struct kvm_vcpu *vcpu)
+{
+	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
+
+	/* Check enablement at VP level */
+	return xc->vp_cam & TM_QW1W2_HO;
+}
+
+bool kvmppc_xive_check_save_restore(struct kvm_vcpu *vcpu)
+{
+	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
+	struct kvmppc_xive *xive = xc->xive;
+
+	if (xive->flags & KVMPPC_XIVE_FLAG_SAVE_RESTORE)
+		return kvmppc_xive_vcpu_has_save_restore(vcpu);
+
+	return true;
+}
+
 /*
  * Push a vcpu's context to the XIVE on guest entry.
  * This assumes we are in virtual mode (MMU on)
@@ -77,7 +96,8 @@ void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu)
 		return;
 
 	eieio();
-	__raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS);
+	if (!kvmppc_xive_vcpu_has_save_restore(vcpu))
+		__raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS);
 	__raw_writel(vcpu->arch.xive_cam_word, tima + TM_QW1_OS + TM_WORD2);
 	vcpu->arch.xive_pushed = 1;
 	eieio();
@@ -149,7 +169,8 @@ void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu)
 	/* First load to pull the context, we ignore the value */
 	__raw_readl(tima + TM_SPC_PULL_OS_CTX);
 	/* Second load to recover the context state (Words 0 and 1) */
-	vcpu->arch.xive_saved_state.w01 = __raw_readq(tima + TM_QW1_OS);
+	if (!kvmppc_xive_vcpu_has_save_restore(vcpu))
+		vcpu->arch.xive_saved_state.w01 = __raw_readq(tima + TM_QW1_OS);
 
 	/* Fixup some of the state for the next load */
 	vcpu->arch.xive_saved_state.lsmfb = 0;
@@ -1319,6 +1340,12 @@ int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
 	if (r)
 		goto bail;
 
+	if (!kvmppc_xive_check_save_restore(vcpu)) {
+		pr_err("inconsistent save-restore setup for VCPU %d\n", cpu);
+		r = -EIO;
+		goto bail;
+	}
+
 	/* Configure VCPU fields for use by assembly push/pull */
 	vcpu->arch.xive_saved_state.w01 = cpu_to_be64(0xff000000);
 	vcpu->arch.xive_cam_word = cpu_to_be32(xc->vp_cam | TM_QW1W2_VO);
@@ -2138,6 +2165,9 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type)
 	if (xive_native_has_single_escalation())
 		xive->flags |= KVMPPC_XIVE_FLAG_SINGLE_ESCALATION;
 
+	if (xive_native_has_save_restore())
+		xive->flags |= KVMPPC_XIVE_FLAG_SAVE_RESTORE;
+
 	kvm->arch.xive = xive;
 	return 0;
 }
diff --git a/arch/powerpc/kvm/book3s_xive.h b/arch/powerpc/kvm/book3s_xive.h
index 73c3cd25093c..e6a9651c6f1e 100644
--- a/arch/powerpc/kvm/book3s_xive.h
+++ b/arch/powerpc/kvm/book3s_xive.h
@@ -98,6 +98,7 @@ struct kvmppc_xive_ops {
 };
 
 #define KVMPPC_XIVE_FLAG_SINGLE_ESCALATION 0x1
+#define KVMPPC_XIVE_FLAG_SAVE_RESTORE 0x2
 
 struct kvmppc_xive {
 	struct kvm *kvm;
@@ -309,6 +310,7 @@ void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu,
 				    struct kvmppc_xive_vcpu *xc, int irq);
 int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp);
 int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive, u64 addr);
+bool kvmppc_xive_check_save_restore(struct kvm_vcpu *vcpu);
 
 static inline bool kvmppc_xive_has_single_escalation(struct kvmppc_xive *xive)
 {
diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c
index 2abb1358a268..af65ea21bde7 100644
--- a/arch/powerpc/kvm/book3s_xive_native.c
+++ b/arch/powerpc/kvm/book3s_xive_native.c
@@ -168,6 +168,12 @@ int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev,
 		goto bail;
 	}
 
+	if (!kvmppc_xive_check_save_restore(vcpu)) {
+		pr_err("inconsistent save-restore setup for VCPU %d\n", server_num);
+		rc = -EIO;
+		goto bail;
+	}
+
 	/*
 	 * Enable the VP first as the single escalation mode will
 	 * affect escalation interrupts numbering
@@ -1114,6 +1120,9 @@ static int kvmppc_xive_native_create(struct kvm_device *dev, u32 type)
 	if (xive_native_has_single_escalation())
 		xive->flags |= KVMPPC_XIVE_FLAG_SINGLE_ESCALATION;
 
+	if (xive_native_has_save_restore())
+		xive->flags |= KVMPPC_XIVE_FLAG_SAVE_RESTORE;
+
 	xive->ops = &kvmppc_xive_native_ops;
 
 	kvm->arch.xive = xive;