4 files changed, 78 insertions, 12 deletions

diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c
index 0e3ae64d3b76..717192915f28 100644
--- a/arch/x86/kernel/cpu/mce/apei.c
+++ b/arch/x86/kernel/cpu/mce/apei.c
@@ -177,16 +177,14 @@ retry:
 	/* no more record */
 	if (*record_id == APEI_ERST_INVALID_RECORD_ID)
 		goto out;
-	rc = erst_read(*record_id, &rcd.hdr, sizeof(rcd));
+	rc = erst_read_record(*record_id, &rcd.hdr, sizeof(rcd), sizeof(rcd),
+			&CPER_CREATOR_MCE);
 	/* someone else has cleared the record, try next one */
 	if (rc == -ENOENT)
 		goto retry;
 	else if (rc < 0)
 		goto out;
-	/* try to skip other type records in storage */
-	else if (rc != sizeof(rcd) ||
-		 !guid_equal(&rcd.hdr.creator_id, &CPER_CREATOR_MCE))
-		goto retry;
+
 	memcpy(m, &rcd.mce, sizeof(*m));
 	rc = sizeof(*m);
 out:
diff --git a/drivers/acpi/apei/erst-dbg.c b/drivers/acpi/apei/erst-dbg.c
index c740f0faad39..8bc71cdc2270 100644
--- a/drivers/acpi/apei/erst-dbg.c
+++ b/drivers/acpi/apei/erst-dbg.c
@@ -111,7 +111,8 @@ retry_next:
 		goto out;
 	}
 retry:
-	rc = len = erst_read(id, erst_dbg_buf, erst_dbg_buf_len);
+	rc = len = erst_read_record(id, erst_dbg_buf, erst_dbg_buf_len,
+			erst_dbg_buf_len, NULL);
 	/* The record may be cleared by others, try read next record */
 	if (rc == -ENOENT)
 		goto retry_next;
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index 698d67cee052..31b077eedb58 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -856,6 +856,74 @@ ssize_t erst_read(u64 record_id, struct cper_record_header *record,
 }
 EXPORT_SYMBOL_GPL(erst_read);
 
+static void erst_clear_cache(u64 record_id)
+{
+	int i;
+	u64 *entries;
+
+	mutex_lock(&erst_record_id_cache.lock);
+
+	entries = erst_record_id_cache.entries;
+	for (i = 0; i < erst_record_id_cache.len; i++) {
+		if (entries[i] == record_id)
+			entries[i] = APEI_ERST_INVALID_RECORD_ID;
+	}
+	__erst_record_id_cache_compact();
+
+	mutex_unlock(&erst_record_id_cache.lock);
+}
+
+ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,
+		size_t buflen, size_t recordlen, const guid_t *creatorid)
+{
+	ssize_t len;
+
+	/*
+	 * if creatorid is NULL, read any record for erst-dbg module
+	 */
+	if (creatorid == NULL) {
+		len = erst_read(record_id, record, buflen);
+		if (len == -ENOENT)
+			erst_clear_cache(record_id);
+
+		return len;
+	}
+
+	len = erst_read(record_id, record, buflen);
+	/*
+	 * if erst_read return value is -ENOENT skip to next record_id,
+	 * and clear the record_id cache.
+	 */
+	if (len == -ENOENT) {
+		erst_clear_cache(record_id);
+		goto out;
+	}
+
+	if (len < 0)
+		goto out;
+
+	/*
+	 * if erst_read return value is less than record head length,
+	 * consider it as -EIO, and clear the record_id cache.
+	 */
+	if (len < recordlen) {
+		len = -EIO;
+		erst_clear_cache(record_id);
+		goto out;
+	}
+
+	/*
+	 * if creatorid is not wanted, consider it as not found,
+	 * for skipping to next record_id.
+	 */
+	if (!guid_equal(&record->creator_id, creatorid))
+		len = -ENOENT;
+
+out:
+	return len;
+}
+EXPORT_SYMBOL_GPL(erst_read_record);
+
 int erst_clear(u64 record_id)
 {
 	int rc, i;
@@ -996,16 +1064,13 @@ skip:
 		goto out;
 	}
 
-	len = erst_read(record_id, &rcd->hdr, rcd_len);
+	len = erst_read_record(record_id, &rcd->hdr, rcd_len, sizeof(*rcd),
+			&CPER_CREATOR_PSTORE);
 	/* The record may be cleared by others, try read next record */
 	if (len == -ENOENT)
 		goto skip;
-	else if (len < 0 || len < sizeof(*rcd)) {
-		rc = -EIO;
+	else if (len < 0)
 		goto out;
-	}
-	if (!guid_equal(&rcd->hdr.creator_id, &CPER_CREATOR_PSTORE))
-		goto skip;
 
 	record->buf = kmalloc(len, GFP_KERNEL);
 	if (record->buf == NULL) {
diff --git a/include/acpi/apei.h b/include/acpi/apei.h
index afaca3a075e8..dc60f7db5524 100644
--- a/include/acpi/apei.h
+++ b/include/acpi/apei.h
@@ -46,6 +46,8 @@ int erst_get_record_id_next(int *pos, u64 *record_id);
 void erst_get_record_id_end(void);
 ssize_t erst_read(u64 record_id, struct cper_record_header *record,
 		  size_t buflen);
+ssize_t erst_read_record(u64 record_id, struct cper_record_header *record,
+		size_t buflen, size_t recordlen, const guid_t *creatorid);
 int erst_clear(u64 record_id);
 
 int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data);