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

["Koralahalli Channabasappa, Smita" <Smita.KoralahalliChannabasappa@amd.com>]

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]