1 files changed, 86 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce-apei.c b/arch/x86/kernel/cpu/mcheck/mce-apei.c
index 4eccd1f..745b54f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-apei.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-apei.c
@@ -8,6 +8,9 @@
  * the error memory page can be offlined by /sbin/mcelog if the error
  * count for one page is beyond the threshold.
  *
+ * For fatal MCE, save MCE record into persistent storage via ERST, so
+ * that the MCE record can be logged after reboot via ERST.
+ *
  * Copyright 2010 Intel Corp.
  *   Author: Huang Ying <ying.huang@intel.com>
  *
@@ -50,3 +53,86 @@ void apei_mce_report_mem_error(int corrected, struct cper_sec_mem_err *mem_err)
 	mce_notify_irq();
 }
 EXPORT_SYMBOL_GPL(apei_mce_report_mem_error);
+
+#define CPER_CREATOR_MCE						\
+	UUID_LE(0x75a574e3, 0x5052, 0x4b29, 0x8a, 0x8e, 0xbe, 0x2c,	\
+		0x64, 0x90, 0xb8, 0x9d)
+#define CPER_SECTION_TYPE_MCE						\
+	UUID_LE(0xfe08ffbe, 0x95e4, 0x4be7, 0xbc, 0x73, 0x40, 0x96,	\
+		0x04, 0x4a, 0x38, 0xfc)
+
+/*
+ * CPER specification (in UEFI specification 2.3 appendix N) requires
+ * byte-packed.
+ */
+struct cper_mce_record {
+	struct cper_record_header hdr;
+	struct cper_section_descriptor sec_hdr;
+	struct mce mce;
+} __packed;
+
+int apei_write_mce(struct mce *m)
+{
+	struct cper_mce_record rcd;
+
+	memset(&rcd, 0, sizeof(rcd));
+	memcpy(rcd.hdr.signature, CPER_SIG_RECORD, CPER_SIG_SIZE);
+	rcd.hdr.revision = CPER_RECORD_REV;
+	rcd.hdr.signature_end = CPER_SIG_END;
+	rcd.hdr.section_count = 1;
+	rcd.hdr.error_severity = CPER_SER_FATAL;
+	/* timestamp, platform_id, partition_id are all invalid */
+	rcd.hdr.validation_bits = 0;
+	rcd.hdr.record_length = sizeof(rcd);
+	rcd.hdr.creator_id = CPER_CREATOR_MCE;
+	rcd.hdr.notification_type = CPER_NOTIFY_MCE;
+	rcd.hdr.record_id = cper_next_record_id();
+	rcd.hdr.flags = CPER_HW_ERROR_FLAGS_PREVERR;
+
+	rcd.sec_hdr.section_offset = (void *)&rcd.mce - (void *)&rcd;
+	rcd.sec_hdr.section_length = sizeof(rcd.mce);
+	rcd.sec_hdr.revision = CPER_SEC_REV;
+	/* fru_id and fru_text is invalid */
+	rcd.sec_hdr.validation_bits = 0;
+	rcd.sec_hdr.flags = CPER_SEC_PRIMARY;
+	rcd.sec_hdr.section_type = CPER_SECTION_TYPE_MCE;
+	rcd.sec_hdr.section_severity = CPER_SER_FATAL;
+
+	memcpy(&rcd.mce, m, sizeof(*m));
+
+	return erst_write(&rcd.hdr);
+}
+
+ssize_t apei_read_mce(struct mce *m, u64 *record_id)
+{
+	struct cper_mce_record rcd;
+	ssize_t len;
+
+	len = erst_read_next(&rcd.hdr, sizeof(rcd));
+	if (len <= 0)
+		return len;
+	/* Can not skip other records in storage via ERST unless clear them */
+	else if (len != sizeof(rcd) ||
+		 uuid_le_cmp(rcd.hdr.creator_id, CPER_CREATOR_MCE)) {
+		if (printk_ratelimit())
+			pr_warning(
+			"MCE-APEI: Can not skip the unknown record in ERST");
+		return -EIO;
+	}
+
+	memcpy(m, &rcd.mce, sizeof(*m));
+	*record_id = rcd.hdr.record_id;
+
+	return sizeof(*m);
+}
+
+/* Check whether there is record in ERST */
+int apei_check_mce(void)
+{
+	return erst_get_record_count();
+}
+
+int apei_clear_mce(u64 record_id)
+{
+	return erst_clear(record_id);
+}