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

[John Garry]

On 30/08/2018 17:34, James Morse wrote:

Hi James,
Zhengqiang no longer works on this topic, so I have cc'ed some more guys 
who should be able to help.

John

Hi Zhengqiang,

On 29/08/18 19:33, Fan Wu wrote:
The current ghes_edac driver does not update per-dimm error
counters when reporting memory errors, because there is no
platform-independent way to find DIMMs based on the error
information provided by firmware. This patch offers a solution
for platforms whose firmwares provide valid module handles
(SMBIOS type 17) in error records. In this case ghes_edac will
use the module handles to locate DIMMs and thus makes per-dimm
error reporting possible.

Does your platform set CPER_MEM_VALID_MODULE_HANDLE in GHES Memory errors? If
so, any chance you could test this patch on your platform? [0]
(original patch: https://lore.kernel.org/patchwork/patch/978928/)

Thanks,

James

[0] https://marc.info/?l=linux-edac&m=152603960002324


diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
index 473aeec..db527f0 100644
--- a/drivers/edac/ghes_edac.c
+++ b/drivers/edac/ghes_edac.c
@@ -81,6 +81,26 @@ static void ghes_edac_count_dimms(const struct dmi_header 
*dh, void *arg)
                (*num_dimm)++;
 }

+static int ghes_edac_dimm_index(u16 handle)
+{
+       struct mem_ctl_info *mci;
+       int i;
+
+       if (!ghes_pvt)
+               return -1;
+
+       mci = ghes_pvt->mci;
+
+       if (!mci)
+               return -1;
+
+       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 +197,8 @@ 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 +349,20 @@ 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);
+               p += sprintf(p, "DIMM DMI handle: 0x%.4x ",
+                            mem_err->mem_dev_handle);
                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 = ghes_edac_dimm_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 */
 };

 /**



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