Re: [PATCH v5 2/3] drm/xe/xe_ras: Report correctable error events to userspace

["Tauro, Riana" <riana.tauro@intel.com>]

On 21-07-2026 14:07, Raag Jadav wrote:
> On Mon, Jul 20, 2026 at 01:52:11PM +0530, Riana Tauro wrote:
>> When an interrupt is received indicating that error counter has crossed
>> its threshold, read the current counter value and deliver a drm_ras error
>> event to userspace for each affected component.
>>
>> To avoid sending duplicate events when the same component appears multiple
>> times in the response. Send the error-event once per component.
> ...
>
>> +void xe_drm_ras_event(struct xe_device *xe, u8 component, u8 severity, u32 value)
>> +{
>> +	struct xe_drm_ras *ras = &xe->ras;
>> +	struct xe_drm_ras_counter *info;
>> +	struct drm_ras_node *node;
>> +	int ret;
>> +
>> +	/* Event is supported only if drm_ras is enabled */
>> +	if (!xe->info.has_drm_ras)
>> +		return;
>> +
>> +	if (component >= DRM_XE_RAS_ERR_COMP_MAX) {
> IIUC this is error_id and should be validated against first/last counter
> range in drm_ras layer (similar to registration code).

This should be done before because we are accessing the nodes here.
The nodes anyway won't be available in xe_drm_ras if not registered with 
drm_ras.



>
>> +		drm_warn(&xe->drm, "unsupported component %u\n", component);
>> +		return;
>> +	}
>> +
>> +	if (severity >= DRM_XE_RAS_ERR_SEV_MAX) {
>> +		drm_warn(&xe->drm, "unsupported severity %u\n", severity);
>> +		return;
>> +	}
>> +
>> +	node = &ras->node[severity];
>> +	info = ras->info[severity];
>> +
>> +	if (!info || !info[component].name)
>> +		return;
>> +
>> +	ret = drm_ras_nl_error_event(node, component, info[component].name, value);
>> +	if (ret)
>> +		drm_err_ratelimited(&xe->drm, "drm_ras error-event failed: %d for %s %s\n", ret,
>> +				    info[component].name, error_severity[severity]);
>> +}
> ...
>
>> +static void ras_send_error_event(struct xe_device *xe, u8 severity, u8 component)
>> +{
>> +	struct xe_ras_error_class counter = {0};
>> +	u8 drm_severity, drm_component;
>> +	u32 value;
>> +	int ret;
>> +
>> +	counter.common.severity = severity;
>> +	counter.common.component = component;
>> +
>> +	ret = get_counter(xe, &counter, &value);
>> +	if (ret)
>> +		return;
>> +
>> +	drm_severity = xe_to_drm_ras_severity(severity);
>> +	drm_component = xe_to_drm_ras_component(component);
>> +
>> +	xe_drm_ras_event(xe, drm_component, drm_severity, value);
>> +}
> This entire function can be dropped. See below.

We don't need to drop function. It's cleaner to have it in the function
than repeating it twice.

>
>>   static u8 handle_core_compute_errors(struct xe_ras_error_array *arr)
>>   {
>>   	struct xe_ras_compute_error *error_info = (void *)arr->details;
>> @@ -312,8 +364,10 @@ void xe_ras_counter_threshold_crossed(struct xe_device *xe,
>>   	struct xe_ras_threshold_crossed *pending = (void *)&response->data;
>>   	struct xe_ras_error_class *errors = pending->counters;
>>   	u32 id, ncounters = pending->ncounters;
>> +	u8 sent = 0;
>>   
>>   	BUILD_BUG_ON(sizeof(response->data) < sizeof(*pending));
>> +	BUILD_BUG_ON(BITS_PER_TYPE(sent) < XE_RAS_COMP_MAX);
>>   	xe_device_assert_mem_access(xe);
>>   
>>   	if (!ncounters || ncounters > XE_RAS_NUM_COUNTERS)
>> @@ -327,8 +381,21 @@ void xe_ras_counter_threshold_crossed(struct xe_device *xe,
>>   		severity = errors[id].common.severity;
>>   		component = errors[id].common.component;
>>   
>> +		if (severity != XE_RAS_SEV_CORRECTABLE) {
>> +			xe_warn(xe, "sysctrl: unexpected severity %s (%u)\n", sev_to_str(severity),
>> +				severity);
> Sanity checks are good, but I think this needs to be extended a bit.
> I have something[1] more robust, feel free to reuse.
>
> [1] https://lore.kernel.org/intel-xe/20260721082953.640497-1-raag.jadav@intel.com

Agreed. I'll drop the checks. We can merge [1] first.
We can drop the drm checks above also if [1] is merged.

Will remove all checks and resend a new version.

>
>> +			continue;
>> +		}
>> +
>>   		xe_warn(xe, "[RAS]: %s %s detected\n",
>>   			comp_to_str(component), sev_to_str(severity));
>> +
>> +		/* Send event once per component */
>> +		if (sent & BIT(component))
>> +			continue;
>> +		sent |= BIT(component);
> With [1] in place you can just get_counter(&counter) and drm_ras_event()
> directly.

Same as above. Better to retain function.

Thanks
Riana


>
> Raag
>
>> +		ras_send_error_event(xe, severity, component);
>>   	}
>>   }
>>   
>> -- 
>> 2.47.1
>>