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Date:   Wed, 16 Jun 2021 20:56:23 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Max Gurtovoy <mgurtovoy@nvidia.com>
Cc:     Alex Williamson <alex.williamson@redhat.com>, cohuck@redhat.com,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        aviadye@nvidia.com, oren@nvidia.com, shahafs@nvidia.com,
        parav@nvidia.com, artemp@nvidia.com, kwankhede@nvidia.com,
        ACurrid@nvidia.com, cjia@nvidia.com, yishaih@nvidia.com,
        kevin.tian@intel.com, hch@infradead.org, targupta@nvidia.com,
        shameerali.kolothum.thodi@huawei.com, liulongfang@huawei.com,
        yan.y.zhao@intel.com
Subject: Re: [PATCH 09/11] PCI: add matching checks for driver_override
 binding
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On Thu, Jun 17, 2021 at 02:51:09AM +0300, Max Gurtovoy wrote:
> 
> On 6/17/2021 2:44 AM, Jason Gunthorpe wrote:
> > On Thu, Jun 17, 2021 at 02:42:46AM +0300, Max Gurtovoy wrote:
> > 
> > > Do you see a reason not adding this alias for stub drivers but
> > > adding it to vfio_pci drivers ?
> > It creates uABI without a userspace user and that is strongly
> > discouraged. The 'stub_pci:' prefix becomes fixed ABI.
> so is it better to have "pci:v*d*sv*sd*bc*sc*i*" for stub drivers ?

No, we don't want to convey any new information about stub drivers to
userspace.

> or not adding alias at all if stub flag is set ?

Yes, just don't change it at all, IMHO.

Jason