[PATCH 4/6 v7] acpi/ghes: Add helper for CXL protocol errors checks

[Hanjun Guo]

On 2025/11/5 2:22, Fabio M. De Francesco wrote:
> Move the CPER CXL protocol errors validity check out of
> cxl_cper_post_prot_err() to new cxl_cper_sec_prot_err_valid() and limit
> the serial number check only to CXL agents that are CXL devices (UEFI
> v2.10, Appendix N.2.13).
> 
> Export the new symbol for reuse by ELOG.
> 
> Signed-off-by: Fabio M. De Francesco <fabio.m.de.francesco at linux.intel.com>
> ---
>   drivers/acpi/apei/ghes.c | 32 ++++++++++++++++++++++----------
>   include/cxl/event.h      | 10 ++++++++++
>   2 files changed, 32 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index d6fe5f020e96..e69ae864f43d 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -706,30 +706,42 @@ static DEFINE_KFIFO(cxl_cper_prot_err_fifo, struct cxl_cper_prot_err_work_data,
>   static DEFINE_SPINLOCK(cxl_cper_prot_err_work_lock);
>   struct work_struct *cxl_cper_prot_err_work;
>   
> -static void cxl_cper_post_prot_err(struct cxl_cper_sec_prot_err *prot_err,
> -				   int severity)
> +int cxl_cper_sec_prot_err_valid(struct cxl_cper_sec_prot_err *prot_err)
>   {
> -	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;
> +		return -EINVAL;
>   	}
>   
>   	if (!(prot_err->valid_bits & PROT_ERR_VALID_ERROR_LOG)) {
>   		pr_err_ratelimited("CXL CPER invalid protocol error log\n");
> -		return;
> +		return -EINVAL;
>   	}
>   
>   	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;
> +		return -EINVAL;
>   	}
>   
> -	if (!(prot_err->valid_bits & PROT_ERR_VALID_SERIAL_NUMBER))
> -		pr_warn(FW_WARN "CXL CPER no device serial number\n");
> +	if ((prot_err->agent_type == RCD || prot_err->agent_type == DEVICE ||
> +	     prot_err->agent_type == LD || prot_err->agent_type == FMLD) &&
> +	    !(prot_err->valid_bits & PROT_ERR_VALID_SERIAL_NUMBER))
> +		pr_warn_ratelimited(FW_WARN
> +				    "CXL CPER no device serial number\n");
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(cxl_cper_sec_prot_err_valid);
> +
> +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 (cxl_cper_sec_prot_err_valid(prot_err))
> +		return;
>   
>   	guard(spinlock_irqsave)(&cxl_cper_prot_err_work_lock);
>   
> diff --git a/include/cxl/event.h b/include/cxl/event.h
> index 6fd90f9cc203..4d7d1036ea9c 100644
> --- a/include/cxl/event.h
> +++ b/include/cxl/event.h
> @@ -320,4 +320,14 @@ static inline int cxl_cper_prot_err_kfifo_get(struct cxl_cper_prot_err_work_data
>   }
>   #endif
>   
> +#ifdef CONFIG_ACPI_APEI_PCIEAER
> +int cxl_cper_sec_prot_err_valid(struct cxl_cper_sec_prot_err *prot_err);
> +#else
> +static inline int
> +cxl_cper_sec_prot_err_valid(struct cxl_cper_sec_prot_err *prot_err)
> +{
> +	return -EOPNOTSUPP;
> +}
> +#endif
> +
>   #endif /* _LINUX_CXL_EVENT_H */

Reviewed-by: Hanjun Guo <guohanjun at huawei.com>

Thanks
Hanjun