From a090931524d03a4975c84b89a32210420d852313 Mon Sep 17 00:00:00 2001 From: Liu Xinpeng Date: Tue, 12 Apr 2022 11:05:19 +0800 Subject: [PATCH] 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: Liu Xinpeng Reviewed-by: Tony Luck Signed-off-by: Rafael J. Wysocki --- arch/x86/kernel/cpu/mce/apei.c | 8 ++-- drivers/acpi/apei/erst-dbg.c | 3 +- drivers/acpi/apei/erst.c | 77 +++++++++++++++++++++++++++++++--- include/acpi/apei.h | 2 + 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 @@ 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: 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 @@ 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; 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 @@ 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) { 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);