[PATCH v2] EDAC, ghes: use CPER module handles to locate DIMMs

[PATCH v2] EDAC, ghes: use CPER module handles to locate DIMMs

[Fan Wu]

For platforms whose firmwares provide valid module handles
(SMBIOS type 17) in error records, this patch uses the module
handles to locate corresponding DIMMs and enables per-DIMM
error counter update.

Signed-off-by: Fan Wu <wufan@codeaurora.org>
---

Changes from v1:
*  Changed the new function name to get_dimm_smbios_index
*  Removed unnecessary checks inside get_dimm_smbios_index
*  Reverted the change of the DMI handle print
*  Updated commit message

---
 drivers/edac/ghes_edac.c | 25 +++++++++++++++++++++++++
 include/linux/edac.h     |  2 ++
 2 files changed, 27 insertions(+)

diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index 473aeec..949f603 100644
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -81,6 +81,20 @@ static void ghes_edac_count_dimms(const struct dmi_header *dh, void *arg)
 		(*num_dimm)++;
 }
 
+static int get_dimm_smbios_index(u16 handle)
+{
+	struct mem_ctl_info *mci;
+	int i;
+
+	mci = ghes_pvt->mci;
+
+	for (i = 0; i < mci->tot_dimms; i++) {
+		if (mci->dimms[i]->smbios_handle == handle)
+			return i;
+	}
+	return -1;
+}
+
 static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
 {
 	struct ghes_edac_dimm_fill *dimm_fill = arg;
@@ -177,6 +191,8 @@ static void ghes_edac_dmidecode(const struct dmi_header *dh, void *arg)
 				entry->total_width, entry->data_width);
 		}
 
+		dimm->smbios_handle = entry->handle;
+
 		dimm_fill->count++;
 	}
 }
@@ -327,12 +343,21 @@ 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;
+
 		dmi_memdev_name(mem_err->mem_dev_handle, &bank, &device);
 		if (bank != NULL && device != NULL)
 			p += sprintf(p, "DIMM location:%s %s ", bank, device);
 		else
 			p += sprintf(p, "DIMM DMI handle: 0x%.4x ",
 				     mem_err->mem_dev_handle);
+
+		index = get_dimm_smbios_index(mem_err->mem_dev_handle);
+		if (index >= 0) {
+			e->top_layer = index;
+			e->enable_per_layer_report = true;
+		}
+
 	}
 	if (p > e->location)
 		*(p - 1) = '\0';
diff --git a/include/linux/edac.h b/include/linux/edac.h
index bffb978..a45ce1f 100644
--- a/include/linux/edac.h
+++ b/include/linux/edac.h
@@ -451,6 +451,8 @@ struct dimm_info {
 	u32 nr_pages;			/* number of pages on this dimm */
 
 	unsigned csrow, cschannel;	/* Points to the old API data */
+
+	u16 smbios_handle;              /* Handle for SMBIOS type 17 */
 };
 
 /**
-- 
2.7.4

Re: [PATCH v2] EDAC, ghes: use CPER module handles to locate DIMMs

[Tyler Baicar]

Hi Fan,

On Thu, Aug 30, 2018 at 2:37 PM, Fan Wu <wufan@codeaurora.org> wrote:
> For platforms whose firmwares provide valid module handles
> (SMBIOS type 17) in error records, this patch uses the module
> handles to locate corresponding DIMMs and enables per-DIMM
> error counter update.
>
> Signed-off-by: Fan Wu <wufan@codeaurora.org>

> diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
> index 473aeec..949f603 100644
> --- a/drivers/edac/ghes_edac.c
> +++ b/drivers/edac/ghes_edac.c
> @@ -81,6 +81,20 @@ static void ghes_edac_count_dimms(const struct dmi_header *dh, void *arg)
>                 (*num_dimm)++;
>  }
>
> +static int get_dimm_smbios_index(u16 handle)
> +{
> +       struct mem_ctl_info *mci;
> +       int i;
> +
> +       mci = ghes_pvt->mci;
> +

Minor nit: you could define and set mci in the same line to save some
space here.

Otherwise this patch looks good to me.

Reviewed-by: Tyler Baicar <baicar.tyler@gmail.com>

RE: [PATCH v2] EDAC, ghes: use CPER module handles to locate DIMMs

[wufan]

Hi Tyler, 

> > +static int get_dimm_smbios_index(u16 handle) {
> > +       struct mem_ctl_info *mci;
> > +       int i;
> > +
> > +       mci = ghes_pvt->mci;
> > +
> 
> Minor nit: you could define and set mci in the same line to save some space
> here.
> 
> Otherwise this patch looks good to me.

Good catch Tyler! I'll fix it.

Thanks,
Fan

> Reviewed-by: Tyler Baicar <baicar.tyler@gmail.com>

Re: [PATCH v2] EDAC, ghes: use CPER module handles to locate DIMMs

[Kani, Toshi]

On Thu, 2018-08-30 at 18:37 +0000, Fan Wu wrote:
> For platforms whose firmwares provide valid module handles
> (SMBIOS type 17) in error records, this patch uses the module
> handles to locate corresponding DIMMs and enables per-DIMM
> error counter update.
> 
> Signed-off-by: Fan Wu <wufan@codeaurora.org>

Tested on an HPE x86 server. It turns out that mem_err->mem_dev_handle
was set to  0 with this FW, and get_dimm_smbios_index() returned -1. But
the code handles this case fine. dimm->smbios_handle's were initialized
properly. So:

Tested-by: Toshi Kani <toshi.kani@hpe.com>

Thanks,
-Toshi