1 files changed, 100 insertions, 0 deletions
diff --git a/drivers/acpi/nfit/mce.c b/drivers/acpi/nfit/mce.c
new file mode 100644
index 000000000..d48a388b7
--- /dev/null
+++ b/drivers/acpi/nfit/mce.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NFIT - Machine Check Handler
+ *
+ * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
+ */
+#include <linux/notifier.h>
+#include <linux/acpi.h>
+#include <linux/nd.h>
+#include <asm/mce.h>
+#include "nfit.h"
+
+static int nfit_handle_mce(struct notifier_block *nb, unsigned long val,
+			void *data)
+{
+	struct mce *mce = (struct mce *)data;
+	struct acpi_nfit_desc *acpi_desc;
+	struct nfit_spa *nfit_spa;
+
+	/* We only care about uncorrectable memory errors */
+	if (!mce_is_memory_error(mce) || mce_is_correctable(mce))
+		return NOTIFY_DONE;
+
+	/* Verify the address reported in the MCE is valid. */
+	if (!mce_usable_address(mce))
+		return NOTIFY_DONE;
+
+	/*
+	 * mce->addr contains the physical addr accessed that caused the
+	 * machine check. We need to walk through the list of NFITs, and see
+	 * if any of them matches that address, and only then start a scrub.
+	 */
+	mutex_lock(&acpi_desc_lock);
+	list_for_each_entry(acpi_desc, &acpi_descs, list) {
+		unsigned int align = 1UL << MCI_MISC_ADDR_LSB(mce->misc);
+		struct device *dev = acpi_desc->dev;
+		int found_match = 0;
+
+		mutex_lock(&acpi_desc->init_mutex);
+		list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
+			struct acpi_nfit_system_address *spa = nfit_spa->spa;
+
+			if (nfit_spa_type(spa) != NFIT_SPA_PM)
+				continue;
+			/* find the spa that covers the mce addr */
+			if (spa->address > mce->addr)
+				continue;
+			if ((spa->address + spa->length - 1) < mce->addr)
+				continue;
+			found_match = 1;
+			dev_dbg(dev, "addr in SPA %d (0x%llx, 0x%llx)\n",
+				spa->range_index, spa->address, spa->length);
+			/*
+			 * We can break at the first match because we're going
+			 * to rescan all the SPA ranges. There shouldn't be any
+			 * aliasing anyway.
+			 */
+			break;
+		}
+		mutex_unlock(&acpi_desc->init_mutex);
+
+		if (!found_match)
+			continue;
+
+		/* If this fails due to an -ENOMEM, there is little we can do */
+		nvdimm_bus_add_badrange(acpi_desc->nvdimm_bus,
+				ALIGN_DOWN(mce->addr, align), align);
+		nvdimm_region_notify(nfit_spa->nd_region,
+				NVDIMM_REVALIDATE_POISON);
+
+		if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) {
+			/*
+			 * We can ignore an -EBUSY here because if an ARS is
+			 * already in progress, just let that be the last
+			 * authoritative one
+			 */
+			acpi_nfit_ars_rescan(acpi_desc, 0);
+		}
+		mce->kflags |= MCE_HANDLED_NFIT;
+		break;
+	}
+
+	mutex_unlock(&acpi_desc_lock);
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block nfit_mce_dec = {
+	.notifier_call	= nfit_handle_mce,
+	.priority	= MCE_PRIO_NFIT,
+};
+
+void nfit_mce_register(void)
+{
+	mce_register_decode_chain(&nfit_mce_dec);
+}
+
+void nfit_mce_unregister(void)
+{
+	mce_unregister_decode_chain(&nfit_mce_dec);
+}