1 files changed, 68 insertions, 5 deletions

diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c
index 79f7d07ef674..ccfd96965630 100644
--- a/arch/powerpc/kvm/book3s_hv_ras.c
+++ b/arch/powerpc/kvm/book3s_hv_ras.c
@@ -65,10 +65,9 @@ static void reload_slb(struct kvm_vcpu *vcpu)
  * On POWER7, see if we can handle a machine check that occurred inside
  * the guest in real mode, without switching to the host partition.
  */
-static void kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
+static long kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 {
 	unsigned long srr1 = vcpu->arch.shregs.msr;
-	struct machine_check_event mce_evt;
 	long handled = 1;
 
 	if (srr1 & SRR1_MC_LDSTERR) {
@@ -106,6 +105,21 @@ static void kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 		handled = 0;
 	}
 
+	return handled;
+}
+
+void kvmppc_realmode_machine_check(struct kvm_vcpu *vcpu)
+{
+	struct machine_check_event mce_evt;
+	long handled;
+
+	if (vcpu->kvm->arch.fwnmi_enabled) {
+		/* FWNMI guests handle their own recovery */
+		handled = 0;
+	} else {
+		handled = kvmppc_realmode_mc_power7(vcpu);
+	}
+
 	/*
 	 * Now get the event and stash it in the vcpu struct so it can
 	 * be handled by the primary thread in virtual mode.  We can't
@@ -122,11 +136,60 @@ static void kvmppc_realmode_mc_power7(struct kvm_vcpu *vcpu)
 	vcpu->arch.mce_evt = mce_evt;
 }
 
-void kvmppc_realmode_machine_check(struct kvm_vcpu *vcpu)
+
+long kvmppc_p9_realmode_hmi_handler(struct kvm_vcpu *vcpu)
 {
-	kvmppc_realmode_mc_power7(vcpu);
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	long ret = 0;
+
+	/*
+	 * Unapply and clear the offset first. That way, if the TB was not
+	 * resynced then it will remain in host-offset, and if it was resynced
+	 * then it is brought into host-offset. Then the tb offset is
+	 * re-applied before continuing with the KVM exit.
+	 *
+	 * This way, we don't need to actually know whether not OPAL resynced
+	 * the timebase or do any of the complicated dance that the P7/8
+	 * path requires.
+	 */
+	if (vc->tb_offset_applied) {
+		u64 new_tb = mftb() - vc->tb_offset_applied;
+		mtspr(SPRN_TBU40, new_tb);
+		if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) {
+			new_tb += 0x1000000;
+			mtspr(SPRN_TBU40, new_tb);
+		}
+		vc->tb_offset_applied = 0;
+	}
+
+	local_paca->hmi_irqs++;
+
+	if (hmi_handle_debugtrig(NULL) >= 0) {
+		ret = 1;
+		goto out;
+	}
+
+	if (ppc_md.hmi_exception_early)
+		ppc_md.hmi_exception_early(NULL);
+
+out:
+	if (vc->tb_offset) {
+		u64 new_tb = mftb() + vc->tb_offset;
+		mtspr(SPRN_TBU40, new_tb);
+		if ((mftb() & 0xffffff) < (new_tb & 0xffffff)) {
+			new_tb += 0x1000000;
+			mtspr(SPRN_TBU40, new_tb);
+		}
+		vc->tb_offset_applied = vc->tb_offset;
+	}
+
+	return ret;
 }
 
+/*
+ * The following subcore HMI handling is all only for pre-POWER9 CPUs.
+ */
+
 /* Check if dynamic split is in force and return subcore size accordingly. */
 static inline int kvmppc_cur_subcore_size(void)
 {
@@ -244,7 +307,7 @@ long kvmppc_realmode_hmi_handler(void)
 {
 	bool resync_req;
 
-	__this_cpu_inc(irq_stat.hmi_exceptions);
+	local_paca->hmi_irqs++;
 
 	if (hmi_handle_debugtrig(NULL) >= 0)
 		return 1;