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

Koralahalli Channabasappa, Smita
2024-12-06T16:16:06Z

Hi Ira,

On 12/2/2024 10:41 AM, Ira Weiny wrote:
> 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()?

Thanks for pointing out. Yes, I will change to memcpy() in next
revision. I think

memcpy() may suit more better here due to consistency and as well addressing

alignment concerns.

Thanks

Smita

>
> Ira
>
> [snip]