1 files changed, 142 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/kvm/book3s_hv_ras.c b/kernel/arch/powerpc/kvm/book3s_hv_ras.c
new file mode 100644
index 000000000..93b5f5c9b
--- /dev/null
+++ b/kernel/arch/powerpc/kvm/book3s_hv_ras.c
@@ -0,0 +1,142 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * Copyright 2012 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/kernel.h>
+#include <asm/opal.h>
+#include <asm/mce.h>
+
+/* SRR1 bits for machine check on POWER7 */
+#define SRR1_MC_LDSTERR		(1ul << (63-42))
+#define SRR1_MC_IFETCH_SH	(63-45)
+#define SRR1_MC_IFETCH_MASK	0x7
+#define SRR1_MC_IFETCH_SLBPAR		2	/* SLB parity error */
+#define SRR1_MC_IFETCH_SLBMULTI		3	/* SLB multi-hit */
+#define SRR1_MC_IFETCH_SLBPARMULTI	4	/* SLB parity + multi-hit */
+#define SRR1_MC_IFETCH_TLBMULTI		5	/* I-TLB multi-hit */
+
+/* DSISR bits for machine check on POWER7 */
+#define DSISR_MC_DERAT_MULTI	0x800		/* D-ERAT multi-hit */
+#define DSISR_MC_TLB_MULTI	0x400		/* D-TLB multi-hit */
+#define DSISR_MC_SLB_PARITY	0x100		/* SLB parity error */
+#define DSISR_MC_SLB_MULTI	0x080		/* SLB multi-hit */
+#define DSISR_MC_SLB_PARMULTI	0x040		/* SLB parity + multi-hit */
+
+/* POWER7 SLB flush and reload */
+static void reload_slb(struct kvm_vcpu *vcpu)
+{
+	struct slb_shadow *slb;
+	unsigned long i, n;
+
+	/* First clear out SLB */
+	asm volatile("slbmte %0,%0; slbia" : : "r" (0));
+
+	/* Do they have an SLB shadow buffer registered? */
+	slb = vcpu->arch.slb_shadow.pinned_addr;
+	if (!slb)
+		return;
+
+	/* Sanity check */
+	n = min_t(u32, be32_to_cpu(slb->persistent), SLB_MIN_SIZE);
+	if ((void *) &slb->save_area[n] > vcpu->arch.slb_shadow.pinned_end)
+		return;
+
+	/* Load up the SLB from that */
+	for (i = 0; i < n; ++i) {
+		unsigned long rb = be64_to_cpu(slb->save_area[i].esid);
+		unsigned long rs = be64_to_cpu(slb->save_area[i].vsid);
+
+		rb = (rb & ~0xFFFul) | i;	/* insert entry number */
+		asm volatile("slbmte %0,%1" : : "r" (rs), "r" (rb));
+	}
+}
+
+/*
+ * On POWER7, see if we can handle a machine check that occurred inside
+ * the guest in real mode, without switching to the host partition.
+ *
+ * Returns: 0 => exit guest, 1 => deliver machine check to guest
+ */
+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) {
+		/* error on load/store */
+		unsigned long dsisr = vcpu->arch.shregs.dsisr;
+
+		if (dsisr & (DSISR_MC_SLB_PARMULTI | DSISR_MC_SLB_MULTI |
+			     DSISR_MC_SLB_PARITY | DSISR_MC_DERAT_MULTI)) {
+			/* flush and reload SLB; flushes D-ERAT too */
+			reload_slb(vcpu);
+			dsisr &= ~(DSISR_MC_SLB_PARMULTI | DSISR_MC_SLB_MULTI |
+				   DSISR_MC_SLB_PARITY | DSISR_MC_DERAT_MULTI);
+		}
+		if (dsisr & DSISR_MC_TLB_MULTI) {
+			if (cur_cpu_spec && cur_cpu_spec->flush_tlb)
+				cur_cpu_spec->flush_tlb(TLB_INVAL_SCOPE_LPID);
+			dsisr &= ~DSISR_MC_TLB_MULTI;
+		}
+		/* Any other errors we don't understand? */
+		if (dsisr & 0xffffffffUL)
+			handled = 0;
+	}
+
+	switch ((srr1 >> SRR1_MC_IFETCH_SH) & SRR1_MC_IFETCH_MASK) {
+	case 0:
+		break;
+	case SRR1_MC_IFETCH_SLBPAR:
+	case SRR1_MC_IFETCH_SLBMULTI:
+	case SRR1_MC_IFETCH_SLBPARMULTI:
+		reload_slb(vcpu);
+		break;
+	case SRR1_MC_IFETCH_TLBMULTI:
+		if (cur_cpu_spec && cur_cpu_spec->flush_tlb)
+			cur_cpu_spec->flush_tlb(TLB_INVAL_SCOPE_LPID);
+		break;
+	default:
+		handled = 0;
+	}
+
+	/*
+	 * See if we have already handled the condition in the linux host.
+	 * We assume that if the condition is recovered then linux host
+	 * will have generated an error log event that we will pick
+	 * up and log later.
+	 * Don't release mce event now. We will queue up the event so that
+	 * we can log the MCE event info on host console.
+	 */
+	if (!get_mce_event(&mce_evt, MCE_EVENT_DONTRELEASE))
+		goto out;
+
+	if (mce_evt.version == MCE_V1 &&
+	    (mce_evt.severity == MCE_SEV_NO_ERROR ||
+	     mce_evt.disposition == MCE_DISPOSITION_RECOVERED))
+		handled = 1;
+
+out:
+	/*
+	 * We are now going enter guest either through machine check
+	 * interrupt (for unhandled errors) or will continue from
+	 * current HSRR0 (for handled errors) in guest. Hence
+	 * queue up the event so that we can log it from host console later.
+	 */
+	machine_check_queue_event();
+
+	return handled;
+}
+
+long kvmppc_realmode_machine_check(struct kvm_vcpu *vcpu)
+{
+	return kvmppc_realmode_mc_power7(vcpu);
+}