Re: [PATCH] edac,ghes,cper: Add Row Extension to Memory Error Record

[Ard Biesheuvel]

On Mon, 27 Jul 2020 at 20:15, Alex Kluver <alex.kluver@xxxxxxx> wrote:
>
> Memory errors could be printed with incorrect row values since the DIMM
> size has outgrown the 16 bit row field in the CPER structure. UEFI
> Specification Version 2.8 has increased the size of row by allowing it to
> use the first 2 bits from a previously reserved space within the structure.
>
> When needed, add the extension bits to the row value printed.
>
> Based on UEFI 2.8 Table 299. Memory Error Record
>
> Tested-by: Russ Anderson <russ.anderson@xxxxxxx>
> Signed-off-by: Alex Kluver <alex.kluver@xxxxxxx>
> ---
>  drivers/edac/ghes_edac.c    | 10 ++++++++--
>  drivers/firmware/efi/cper.c | 11 +++++++++--
>  include/linux/cper.h        |  9 +++++++--
>  3 files changed, 24 insertions(+), 6 deletions(-)
>

Unless any of the EDAC folks object, I will take this as a fix via the EFI tree.

Thanks,
Ard.


> diff --git a/drivers/edac/ghes_edac.c b/drivers/edac/ghes_edac.c
> index cb3dab56a875..cfa3156300f5 100644
> --- a/drivers/edac/ghes_edac.c
> +++ b/drivers/edac/ghes_edac.c
> @@ -337,8 +337,14 @@ void ghes_edac_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
>                 p += sprintf(p, "rank:%d ", mem_err->rank);
>         if (mem_err->validation_bits & CPER_MEM_VALID_BANK)
>                 p += sprintf(p, "bank:%d ", mem_err->bank);
> -       if (mem_err->validation_bits & CPER_MEM_VALID_ROW)
> -               p += sprintf(p, "row:%d ", mem_err->row);
> +       if (mem_err->validation_bits & (CPER_MEM_VALID_ROW | CPER_MEM_VALID_ROW_EXT)) {
> +               u32 row_extended = 0;
> +               if (mem_err->validation_bits & CPER_MEM_VALID_ROW_EXT)
> +                       row_extended = (mem_err->extended & CPER_MEM_EXT_ROW_MASK)
> +                               <<CPER_MEM_EXT_ROW_SHIFT;
> +               row_extended |= mem_err->row;
> +               p += sprintf(p, "row:%d ", row_extended);
> +       }
>         if (mem_err->validation_bits & CPER_MEM_VALID_COLUMN)
>                 p += sprintf(p, "col:%d ", mem_err->column);
>         if (mem_err->validation_bits & CPER_MEM_VALID_BIT_POSITION)
> diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c
> index f564e15fbc7e..5faaf6ecd659 100644
> --- a/drivers/firmware/efi/cper.c
> +++ b/drivers/firmware/efi/cper.c
> @@ -234,8 +234,14 @@ static int cper_mem_err_location(struct cper_mem_err_compact *mem, char *msg)
>                 n += scnprintf(msg + n, len - n, "bank: %d ", mem->bank);
>         if (mem->validation_bits & CPER_MEM_VALID_DEVICE)
>                 n += scnprintf(msg + n, len - n, "device: %d ", mem->device);
> -       if (mem->validation_bits & CPER_MEM_VALID_ROW)
> -               n += scnprintf(msg + n, len - n, "row: %d ", mem->row);
> +       if (mem->validation_bits & (CPER_MEM_VALID_ROW | CPER_MEM_VALID_ROW_EXT)) {
> +               u32 row_extended = 0;
> +               if (mem->validation_bits & CPER_MEM_VALID_ROW_EXT)
> +                       row_extended = (mem->extended & CPER_MEM_EXT_ROW_MASK)
> +                               <<CPER_MEM_EXT_ROW_SHIFT;
> +               row_extended |= mem->row;
> +               n += scnprintf(msg + n, len - n, "row: %d ", row_extended);
> +       }
>         if (mem->validation_bits & CPER_MEM_VALID_COLUMN)
>                 n += scnprintf(msg + n, len - n, "column: %d ", mem->column);
>         if (mem->validation_bits & CPER_MEM_VALID_BIT_POSITION)
> @@ -292,6 +298,7 @@ void cper_mem_err_pack(const struct cper_sec_mem_err *mem,
>         cmem->requestor_id = mem->requestor_id;
>         cmem->responder_id = mem->responder_id;
>         cmem->target_id = mem->target_id;
> +       cmem->extended = mem->extended;
>         cmem->rank = mem->rank;
>         cmem->mem_array_handle = mem->mem_array_handle;
>         cmem->mem_dev_handle = mem->mem_dev_handle;
> diff --git a/include/linux/cper.h b/include/linux/cper.h
> index 8537e9282a65..c8313753ee49 100644
> --- a/include/linux/cper.h
> +++ b/include/linux/cper.h
> @@ -230,6 +230,10 @@ enum {
>  #define CPER_MEM_VALID_RANK_NUMBER             0x8000
>  #define CPER_MEM_VALID_CARD_HANDLE             0x10000
>  #define CPER_MEM_VALID_MODULE_HANDLE           0x20000
> +#define CPER_MEM_VALID_ROW_EXT                 0x40000
> +
> +#define CPER_MEM_EXT_ROW_MASK                  0x3
> +#define CPER_MEM_EXT_ROW_SHIFT                 16
>
>  #define CPER_PCIE_VALID_PORT_TYPE              0x0001
>  #define CPER_PCIE_VALID_VERSION                        0x0002
> @@ -443,7 +447,7 @@ struct cper_sec_mem_err_old {
>         u8      error_type;
>  };
>
> -/* Memory Error Section (UEFI >= v2.3), UEFI v2.7 sec N.2.5 */
> +/* Memory Error Section (UEFI >= v2.3), UEFI v2.8 sec N.2.5 */
>  struct cper_sec_mem_err {
>         u64     validation_bits;
>         u64     error_status;
> @@ -461,7 +465,7 @@ struct cper_sec_mem_err {
>         u64     responder_id;
>         u64     target_id;
>         u8      error_type;
> -       u8      reserved;
> +       u8      extended;
>         u16     rank;
>         u16     mem_array_handle;       /* "card handle" in UEFI 2.4 */
>         u16     mem_dev_handle;         /* "module handle" in UEFI 2.4 */
> @@ -483,6 +487,7 @@ struct cper_mem_err_compact {
>         u16     rank;
>         u16     mem_array_handle;
>         u16     mem_dev_handle;
> +       u8      extended;
>  };
>
>  /* PCI Express Error Section, UEFI v2.7 sec N.2.7 */