Re: [RFC PATCH v10 0/5] fix vt-d hard lockup when hotplug ATS capable device

Baolu Lu
2024-01-18T00:52:20Z

On 1/17/24 5:00 PM, Ethan Zhao wrote:
> +       /*
> +        * If the ATS invalidation target device is gone this moment
> (surprise
> +        * removed, died, no response) don't try this request again. this
> +        * request will not get valid result anymore. but the request was
> +        * already submitted to hardware and we predict to get a ITE in
> +        * followed batch of request, if so, it will get handled then.
> +        */
> +       if (target_pdev && !pci_device_is_present(target_pdev))
> +               return -EINVAL;

Again, we should not ignore the error triggered by the current request.
Do not leave it to the next one. The WAIT descriptor is a fence. Handle
everything within its boundary.

Best regards,
baolu