Commit a0909315 authored by Liu Xinpeng's avatar Liu Xinpeng Committed by Rafael J. Wysocki
Browse files

ACPI: APEI: Fix missing ERST record id 



Read a record is cleared by others, but the deleted record cache entry is
still created by erst_get_record_id_next. When next enumerate the records,
get the cached deleted record, then erst_read() return -ENOENT and try to
get next record, loop back to first ID will return 0 in function
__erst_record_id_cache_add_one and then set record_id as
APEI_ERST_INVALID_RECORD_ID, finished this time read operation.
It will result in read the records just in the cache hereafter.

This patch cleared the deleted record cache, fix the issue that
"./erst-inject -p" shows record counts not equal to "./erst-inject -n".

A reproducer of the problem(retry many times):

[root@localhost erst-inject]# ./erst-inject -c 0xaaaaa00011
[root@localhost erst-inject]# ./erst-inject -p
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00012
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00013
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00014
[root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000006
[root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000007
[root@localhost erst-inject]# ./erst-inject -i 0xaaaaa000008
[root@localhost erst-inject]# ./erst-inject -p
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00012
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00013
rc: 273
rcd sig: CPER
rcd id: 0xaaaaa00014
[root@localhost erst-inject]# ./erst-inject -n
total error record count: 6

Signed-off-by: default avatarLiu Xinpeng <liuxp11@chinatelecom.cn>
Reviewed-by: default avatarTony Luck <tony.luck@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent ce522ba9

arch/x86/kernel/cpu/mce/apei.c

+3 −5
Original line number Diff line number Diff line
@@ -177,16 +177,14 @@ ssize_t apei_read_mce(struct mce *m, u64 *record_id) 
	/* 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:

drivers/acpi/apei/erst-dbg.c

+2 −1
Original line number Diff line number Diff line
@@ -111,7 +111,8 @@ static ssize_t erst_dbg_read(struct file *filp, char __user *ubuf, 
		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;

drivers/acpi/apei/erst.c

+71 −6
Original line number Diff line number Diff line
@@ -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 @@ static ssize_t erst_reader(struct pstore_record *record) 
		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) {

include/acpi/apei.h

+2 −0
Original line number Diff line number Diff line
@@ -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);