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From:   Cornelia Huck <cohuck@redhat.com>
To:     Alex Williamson <alex.williamson@redhat.com>,
        Jason Gunthorpe <jgg@nvidia.com>
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        shameerali.kolothum.thodi@huawei.com, kevin.tian@intel.com,
        yishaih@nvidia.com, linux-doc@vger.kernel.org, corbet@lwn.net
Subject: Re: [PATCH v3] vfio-pci: Provide reviewers and acceptance criteria
 for vendor drivers
In-Reply-To: <20220315102200.15a86b16.alex.williamson@redhat.com>
Organization: Red Hat GmbH
References: <164728932975.54581.1235687116658126625.stgit@omen>
 <87a6drh8hy.fsf@redhat.com> <20220315155304.GC11336@nvidia.com>
 <20220315102200.15a86b16.alex.williamson@redhat.com>
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Date:   Tue, 15 Mar 2022 18:32:14 +0100
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On Tue, Mar 15 2022, Alex Williamson <alex.williamson@redhat.com> wrote:

> On Tue, 15 Mar 2022 12:53:04 -0300
> Jason Gunthorpe <jgg@nvidia.com> wrote:
>
>> On Tue, Mar 15, 2022 at 10:26:17AM +0100, Cornelia Huck wrote:
>> > On Mon, Mar 14 2022, Alex Williamson <alex.williamson@redhat.com> wrote:

>> In general I wonder if this is a bit too specific to PCI, really this
>> is just review criteria for any driver making a struct vfio_device_ops
>> implementation, and we have some specific guidance for migration here
>> as well.
>> 
>> Like if IBM makes s390 migration drivers all of this applies just as
>> well even though they are not PCI.
>
> Are you volunteering to be a reviewer under drivers/vfio/?  Careful,
> I'll add you ;)
>
> What you're saying is true of course and it could be argued that this
> sort of criteria is true for any new driver, I think the unique thing
> here that raises it to a point where we want to formalize the breadth
> of reviews is how significantly lower the bar is to create a device
> specific driver now that we have a vfio-pci-core library.  Shameer's
> stub driver is 100 LoC.  I also expect that the pool of people willing
> to volunteer to be reviewers for PCI related device specific drivers is
> large than we might see for arbitrary drivers.

Yes. Also, I expect that more people understand how a PCI driver works
than how an s390 channel subsystem driver works :)

I think we'll just have to hope that attempts to add e.g. migration
support to a driver outside of vfio-pci show up on the correct mailing
lists and that the right people notice it or can be pointed towards it.

>
>> > > +New driver submissions are therefore requested to have approval via
>> > > +Sign-off/Acked-by/etc for any interactions with parent drivers.  
>> > 
>> > s/Sign-off/Reviewed-by/ ?
>> > 
>> > I would not generally expect the reviewers listed to sign off on other
>> > people's patches.  
>> 
>> It happens quite a lot when those people help write the patches too :)
>
> This is what "etc" is for, the owners are involved and have endorsed it
> in some way, that's all we care about.

Fair enough.