Re: [PATCH v18 10/11] PCI/DPC: Add Error Disconnect Recover (EDR) support

[Kuppuswamy, Sathyanarayanan]

Hi Bjorn,

On 3/24/20 2:37 PM, Bjorn Helgaas wrote:
> This is really ugly.  What's the story on this firmware?  It sounds
> defective to me.
I think there is no defined standard for this. I have checked few
_DSM implementations. Some of them return default value and some
don't. But atleast in the test hardware I use, we need this check.

> Or is everybody that uses _DSM supposed to check before evaluating it?
I think its safer to do this check.
> E.g.,
>
>    if (!acpi_check_dsm(...))
>      return -EINVAL;
>
>    obj = acpi_evaluate_dsm(...);
>
> If everybody is supposed to do this, it seems like the check part
> should be moved into acpi_evaluate_dsm().