lkml.org 
[lkml]   [2020]   [Jun]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 01/18] nitro_enclaves: Add ioctl interface definition
On Mon, Jun 01, 2020 at 10:20:18AM +0300, Paraschiv, Andra-Irina wrote:
>
>
> On 01/06/2020 06:02, Benjamin Herrenschmidt wrote:
> > On Wed, 2020-05-27 at 09:49 +0100, Stefan Hajnoczi wrote:
> > > What about feature bits or a API version number field? If you add
> > > features to the NE driver, how will userspace detect them?
> > >
> > > Even if you intend to always compile userspace against the exact kernel
> > > headers that the program will run on, it can still be useful to have an
> > > API version for informational purposes and to easily prevent user
> > > errors (running a new userspace binary on an old kernel where the API is
> > > different).
> > >
> > > Finally, reserved struct fields may come in handy in the future. That
> > > way userspace and the kernel don't need to explicitly handle multiple
> > > struct sizes.
> > Beware, Greg might disagree :)
> >
> > That said, yes, at least a way to query the API version would be
> > useful.
>
> I see there are several thoughts with regard to extensions possibilities. :)
>
> I added an ioctl for getting the API version, we have now a way to query
> that info. Also, I updated the sample in this patch series to check for the
> API version.

Great. The ideas are orthogonal and not all of them need to be used
together. As long as their is a way of extending the API cleanly in the
future then extensions can be made without breaking userspace.

Stefan
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2020-06-05 10:15    [W:1.163 / U:0.076 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site