diff mbox series

[v4] EDAC/ghes: Setup DIMM label from DMI and use it in error reports

Message ID 20200528101307.23245-1-rrichter@marvell.com (mailing list archive)
State New, archived
Headers show
Series [v4] EDAC/ghes: Setup DIMM label from DMI and use it in error reports | expand

Commit Message

Robert Richter May 28, 2020, 10:13 a.m. UTC
The ghes driver reports errors with 'unknown label' even if the actual
DIMM label is known, e.g.:

 EDAC MC0: 1 CE Single-bit ECC on unknown label (node:0 card:0
   module:0 rank:1 bank:0 col:13 bit_pos:16 DIMM location:N0 DIMM_A0
   page:0x966a9b3 offset:0x0 grain:1 syndrome:0x0 - APEI location:
   node:0 card:0 module:0 rank:1 bank:0 col:13 bit_pos:16 DIMM
   location:N0 DIMM_A0 status(0x0000000000000400): Storage error in
   DRAM memory)

Fix this by using struct dimm_info's label string in error reports:

 EDAC MC0: 1 CE Single-bit ECC on N0 DIMM_A0 (node:0 card:0 module:0
   rank:1 bank:515 col:14 bit_pos:16 DIMM location:N0 DIMM_A0
   page:0x99223d8 offset:0x0 grain:1 syndrome:0x0 - APEI location:
   node:0 card:0 module:0 rank:1 bank:515 col:14 bit_pos:16 DIMM
   location:N0 DIMM_A0 status(0x0000000000000400): Storage error in
   DRAM memory)

The labels are initialized by reading the bank and device strings from
DMI. Now, the label information can also read from sysfs. E.g. a
ThunderX2 system will show the following:

 /sys/devices/system/edac/mc/mc0/dimm0/dimm_label:N0 DIMM_A0
 /sys/devices/system/edac/mc/mc0/dimm1/dimm_label:N0 DIMM_B0
 /sys/devices/system/edac/mc/mc0/dimm2/dimm_label:N0 DIMM_C0
 /sys/devices/system/edac/mc/mc0/dimm3/dimm_label:N0 DIMM_D0
 /sys/devices/system/edac/mc/mc0/dimm4/dimm_label:N0 DIMM_E0
 /sys/devices/system/edac/mc/mc0/dimm5/dimm_label:N0 DIMM_F0
 /sys/devices/system/edac/mc/mc0/dimm6/dimm_label:N0 DIMM_G0
 /sys/devices/system/edac/mc/mc0/dimm7/dimm_label:N0 DIMM_H0
 /sys/devices/system/edac/mc/mc0/dimm8/dimm_label:N1 DIMM_I0
 /sys/devices/system/edac/mc/mc0/dimm9/dimm_label:N1 DIMM_J0
 /sys/devices/system/edac/mc/mc0/dimm10/dimm_label:N1 DIMM_K0
 /sys/devices/system/edac/mc/mc0/dimm11/dimm_label:N1 DIMM_L0
 /sys/devices/system/edac/mc/mc0/dimm12/dimm_label:N1 DIMM_M0
 /sys/devices/system/edac/mc/mc0/dimm13/dimm_label:N1 DIMM_N0
 /sys/devices/system/edac/mc/mc0/dimm14/dimm_label:N1 DIMM_O0
 /sys/devices/system/edac/mc/mc0/dimm15/dimm_label:N1 DIMM_P0

Since dimm_labels can be rewritten, that label will be used in a later
error report:

 # echo foobar >/sys/devices/system/edac/mc/mc0/dimm0/dimm_label
 # # some error injection here
 # dmesg | grep foobar
 [ 751.383533] EDAC MC0: 1 CE Single-bit ECC on foobar (node:0 card:0
 module:0 rank:1 bank:259 col:3 bit_pos:16 DIMM location:N0 DIMM_A0
 page:0x8c8dc74 offset:0x0 grain:1 syndrome:0x0 - APEI location:
 node:0 card:0 module:0 rank:1 bank:259 col:3 bit_pos:16 DIMM
 location:N0 DIMM_A0 status(0x0000000000000400): Storage error in DRAM
 memory)

Signed-off-by: Robert Richter <rrichter@marvell.com>
---
v4:

 * dimm->label: Only update dimm->label in if bank/device is found in
   the SMBIOS table, this keeps current behavior for machines that do
   not provide this information.

 * e->location: Keep current behavior how e->location is written.

 * e->label: Use dimm->label if a DIMM was found by its handle and
   "unknown memory" otherwise. This aligns with the edac_mc
   implementation.

Signed-off-by: Robert Richter <rrichter@marvell.com>
---
 drivers/edac/ghes_edac.c | 37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

Comments

Borislav Petkov June 2, 2020, 3:48 p.m. UTC | #1
On Thu, May 28, 2020 at 12:13:06PM +0200, Robert Richter wrote:
> The ghes driver reports errors with 'unknown label' even if the actual
> DIMM label is known, e.g.:
> 
>  EDAC MC0: 1 CE Single-bit ECC on unknown label (node:0 card:0
>    module:0 rank:1 bank:0 col:13 bit_pos:16 DIMM location:N0 DIMM_A0
>    page:0x966a9b3 offset:0x0 grain:1 syndrome:0x0 - APEI location:
>    node:0 card:0 module:0 rank:1 bank:0 col:13 bit_pos:16 DIMM
>    location:N0 DIMM_A0 status(0x0000000000000400): Storage error in
>    DRAM memory)
> 
> Fix this by using struct dimm_info's label string in error reports:
> 
>  EDAC MC0: 1 CE Single-bit ECC on N0 DIMM_A0 (node:0 card:0 module:0
>    rank:1 bank:515 col:14 bit_pos:16 DIMM location:N0 DIMM_A0
>    page:0x99223d8 offset:0x0 grain:1 syndrome:0x0 - APEI location:
>    node:0 card:0 module:0 rank:1 bank:515 col:14 bit_pos:16 DIMM
>    location:N0 DIMM_A0 status(0x0000000000000400): Storage error in
>    DRAM memory)
> 
> The labels are initialized by reading the bank and device strings from
> DMI. Now, the label information can also read from sysfs. E.g. a
> ThunderX2 system will show the following:
> 
>  /sys/devices/system/edac/mc/mc0/dimm0/dimm_label:N0 DIMM_A0
>  /sys/devices/system/edac/mc/mc0/dimm1/dimm_label:N0 DIMM_B0
>  /sys/devices/system/edac/mc/mc0/dimm2/dimm_label:N0 DIMM_C0
>  /sys/devices/system/edac/mc/mc0/dimm3/dimm_label:N0 DIMM_D0
>  /sys/devices/system/edac/mc/mc0/dimm4/dimm_label:N0 DIMM_E0
>  /sys/devices/system/edac/mc/mc0/dimm5/dimm_label:N0 DIMM_F0
>  /sys/devices/system/edac/mc/mc0/dimm6/dimm_label:N0 DIMM_G0
>  /sys/devices/system/edac/mc/mc0/dimm7/dimm_label:N0 DIMM_H0
>  /sys/devices/system/edac/mc/mc0/dimm8/dimm_label:N1 DIMM_I0
>  /sys/devices/system/edac/mc/mc0/dimm9/dimm_label:N1 DIMM_J0
>  /sys/devices/system/edac/mc/mc0/dimm10/dimm_label:N1 DIMM_K0
>  /sys/devices/system/edac/mc/mc0/dimm11/dimm_label:N1 DIMM_L0
>  /sys/devices/system/edac/mc/mc0/dimm12/dimm_label:N1 DIMM_M0
>  /sys/devices/system/edac/mc/mc0/dimm13/dimm_label:N1 DIMM_N0
>  /sys/devices/system/edac/mc/mc0/dimm14/dimm_label:N1 DIMM_O0
>  /sys/devices/system/edac/mc/mc0/dimm15/dimm_label:N1 DIMM_P0
> 
> Since dimm_labels can be rewritten, that label will be used in a later
> error report:
> 
>  # echo foobar >/sys/devices/system/edac/mc/mc0/dimm0/dimm_label
>  # # some error injection here
>  # dmesg | grep foobar
>  [ 751.383533] EDAC MC0: 1 CE Single-bit ECC on foobar (node:0 card:0
>  module:0 rank:1 bank:259 col:3 bit_pos:16 DIMM location:N0 DIMM_A0
>  page:0x8c8dc74 offset:0x0 grain:1 syndrome:0x0 - APEI location:
>  node:0 card:0 module:0 rank:1 bank:259 col:3 bit_pos:16 DIMM
>  location:N0 DIMM_A0 status(0x0000000000000400): Storage error in DRAM
>  memory)
> 
> Signed-off-by: Robert Richter <rrichter@marvell.com>
> ---
> v4:
> 
>  * dimm->label: Only update dimm->label in if bank/device is found in
>    the SMBIOS table, this keeps current behavior for machines that do
>    not provide this information.
> 
>  * e->location: Keep current behavior how e->location is written.
> 
>  * e->label: Use dimm->label if a DIMM was found by its handle and
>    "unknown memory" otherwise. This aligns with the edac_mc
>    implementation.
> 
> Signed-off-by: Robert Richter <rrichter@marvell.com>
> ---
>  drivers/edac/ghes_edac.c | 37 ++++++++++++++++++++++++++-----------
>  1 file changed, 26 insertions(+), 11 deletions(-)

Yap, looks good. I'll queue it after the merge window.

Thx.
Robert Richter June 3, 2020, 6:56 a.m. UTC | #2
On 02.06.20 17:48:43, Borislav Petkov wrote:
> On Thu, May 28, 2020 at 12:13:06PM +0200, Robert Richter wrote:

> > v4:
> > 
> >  * dimm->label: Only update dimm->label in if bank/device is found in
> >    the SMBIOS table, this keeps current behavior for machines that do
> >    not provide this information.
> > 
> >  * e->location: Keep current behavior how e->location is written.
> > 
> >  * e->label: Use dimm->label if a DIMM was found by its handle and
> >    "unknown memory" otherwise. This aligns with the edac_mc
> >    implementation.
> > 
> > Signed-off-by: Robert Richter <rrichter@marvell.com>
> > ---
> >  drivers/edac/ghes_edac.c | 37 ++++++++++++++++++++++++++-----------
> >  1 file changed, 26 insertions(+), 11 deletions(-)
> 
> Yap, looks good. I'll queue it after the merge window.

Great, thanks.

-Robert
diff mbox series

Patch

diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index cb3dab56a875..9a6a055ab624 100644
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -87,16 +87,29 @@  static void ghes_edac_count_dimms(const struct dmi_header *dh, void *arg)
 		(*num_dimm)++;
 }
 
-static int get_dimm_smbios_index(struct mem_ctl_info *mci, u16 handle)
+static struct dimm_info *find_dimm_by_handle(struct mem_ctl_info *mci, u16 handle)
 {
 	struct dimm_info *dimm;
 
 	mci_for_each_dimm(mci, dimm) {
 		if (dimm->smbios_handle == handle)
-			return dimm->idx;
+			return dimm;
 	}
 
-	return -1;
+	return NULL;
+}
+
+static void dimm_setup_label(struct dimm_info *dimm, u16 handle)
+{
+	const char *bank = NULL, *device = NULL;
+
+	dmi_memdev_name(handle, &bank, &device);
+
+	/* both strings must be non-zero */
+	if (bank && *bank && device && *device) {
+		snprintf(dimm->label, sizeof(dimm->label),
+			"%s %s", bank, device);
+	}
 }
 
 static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
@@ -179,9 +192,7 @@  static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
 		dimm->dtype = DEV_UNKNOWN;
 		dimm->grain = 128;		/* Likely, worse case */
 
-		/*
-		 * FIXME: It shouldn't be hard to also fill the DIMM labels
-		 */
+		dimm_setup_label(dimm, entry->handle);
 
 		if (dimm->nr_pages) {
 			edac_dbg(1, "DIMM%i: %s size = %d MB%s\n",
@@ -228,7 +239,6 @@  void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
 	memset(e, 0, sizeof (*e));
 	e->error_count = 1;
 	e->grain = 1;
-	strcpy(e->label, "unknown label");
 	e->msg = pvt->msg;
 	e->other_detail = pvt->other_detail;
 	e->top_layer = -1;
@@ -345,7 +355,7 @@  void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
 		p += sprintf(p, "bit_pos:%d ", mem_err->bit_pos);
 	if (mem_err->validation_bits & CPER_MEM_VALID_MODULE_HANDLE) {
 		const char *bank = NULL, *device = NULL;
-		int index = -1;
+		struct dimm_info *dimm;
 
 		dmi_memdev_name(mem_err->mem_dev_handle, &bank, &device);
 		if (bank != NULL && device != NULL)
@@ -354,13 +364,18 @@  void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
 			p += sprintf(p, "DIMM DMI handle: 0x%.4x ",
 				     mem_err->mem_dev_handle);
 
-		index = get_dimm_smbios_index(mci, mem_err->mem_dev_handle);
-		if (index >= 0)
-			e->top_layer = index;
+		dimm = find_dimm_by_handle(mci, mem_err->mem_dev_handle);
+		if (dimm) {
+			e->top_layer = dimm->idx;
+			strcpy(e->label, dimm->label);
+		}
 	}
 	if (p > e->location)
 		*(p - 1) = '\0';
 
+	if (!*e->label)
+		strcpy(e->label, "unknown memory");
+
 	/* All other fields are mapped on e->other_detail */
 	p = pvt->other_detail;
 	p += snprintf(p, sizeof(pvt->other_detail),