RE: [PATCH Part2 v6 02/49] iommu/amd: Introduce function to check SEV-SNP support

From: Kalra, Ashish
Date: Fri Aug 26 2022 - 14:57:25 EST


[AMD Official Use Only - General]

Hello Jarkko,

>>
>> It really should be, in order to have any practical use:
>>
>> if (no_iommu) {
>> pr_err("SEV-SNP: IOMMU is disabled.\n");
>> return false;
>> }
>>
>> if (iommu_default_passthrough()) {
>> pr_err("SEV-SNP: IOMMU is configured in passthrough mode.\n");
>> return false;
>> }
>>
>> The comment is *completely* redundant, it absolutely does not serve
>> any sane purpose. It just tells what the code already clearly stating.
>>
>> The combo error message on the other hand leaves you to the question
>> "which one was it", and for that reason combining the checks leaves
>> you to a louse debugging experience.

>Also, are those really *errors*? That implies that there is something wrong.

>Since you can have a legit configuration, IMHO they should be either warn or info. What do you think?

>They are definitely not errors

Yes, they can be warn or info, but as I mentioned above this patch is now part of IOMMU + SNP series,
so these comments are now relevant for that.

Thanks,
Ashish