Re: [PATCH v3 6/7] acpi/ghes, cper: Recognize and cache CXL Protocol errors

Ira Weiny
2024-12-02T18:42:09Z

Smita Koralahalli wrote:
> Add support in GHES to detect and process CXL CPER Protocol errors, as
> defined in UEFI v2.10, section N.2.13.
>
> Define struct cxl_cper_prot_err_work_data to cache CXL protocol error
> information, including RAS capabilities and severity, for further
> handling.
>
> These cached CXL CPER records will later be processed by workqueues
> within the CXL subsystem.
>
> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
> ---
> drivers/acpi/apei/ghes.c | 52 ++++++++++++++++++++++++++++++++++++++++
> include/cxl/event.h | 6 +++++
> 2 files changed, 58 insertions(+)
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 62ffe6eb5503..6cd9d5375d7c 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -676,6 +676,54 @@ static void ghes_defer_non_standard_event(struct acpi_hest_generic_data *gdata,
> schedule_work(&entry->work);
> }
>
> +static void cxl_cper_post_prot_err(struct cxl_cper_sec_prot_err *prot_err,
> + int severity)
> +{
> + struct cxl_cper_prot_err_work_data wd;
> + u8 *dvsec_start, *cap_start;
> +
> + if (!(prot_err->valid_bits & PROT_ERR_VALID_AGENT_ADDRESS)) {
> + pr_err_ratelimited("CXL CPER invalid agent type\n");
> + return;
> + }
> +
> + if (!(prot_err->valid_bits & PROT_ERR_VALID_ERROR_LOG)) {
> + pr_err_ratelimited("CXL CPER invalid protocol error log\n");
> + return;
> + }
> +
> + if (prot_err->err_len != sizeof(struct cxl_ras_capability_regs)) {
> + pr_err_ratelimited("CXL CPER invalid RAS Cap size (%u)\n",
> + prot_err->err_len);
> + return;
> + }
> +
> + if (!(prot_err->valid_bits & PROT_ERR_VALID_SERIAL_NUMBER))
> + pr_warn(FW_WARN "CXL CPER no device serial number\n");
> +
> + switch (prot_err->agent_type) {
> + case RCD:
> + case DEVICE:
> + case LD:
> + case FMLD:
> + case RP:
> + case DSP:
> + case USP:
> + memcpy(&wd.prot_err, prot_err, sizeof(wd.prot_err));
> +
> + dvsec_start = (u8 *)(prot_err + 1);
> + cap_start = dvsec_start + prot_err->dvsec_len;
> +
> + wd.ras_cap = *(struct cxl_ras_capability_regs *)cap_start;

Why not memcpy()?

Ira

[snip]