[Libva] [PATCH] drm: remove va_drm_is_authenticated check

[Xiang, Haihao]

>-----Original Message-----
>From: Sean V Kelley [mailto:seanvk at posteo.de]
>Sent: Friday, November 18, 2016 12:47 AM
>To: Emil Velikov <emil.l.velikov at gmail.com>; Xiang, Haihao
><haihao.xiang at intel.com>
>Cc: Daniel Vetter <daniel.vetter at ffwll.ch>; libva at lists.freedesktop.org; David
>Herrmann <dh.herrmann at gmail.com>
>Subject: Re: [Libva] [PATCH] drm: remove va_drm_is_authenticated check
>
>On Thu, 2016-11-17 at 16:42 +0000, Emil Velikov wrote:
>> On 17 November 2016 at 15:38, Xiang, Haihao <haihao.xiang at intel.com>
>> wrote:
>> > > From: Libva [mailto:libva-bounces at lists.freedesktop.org] On Behalf
>> > > Of Emil Velikov
>> > > Sent: Tuesday, November 15, 2016 11:24 PM
>> > > To: libva at lists.freedesktop.org
>> > > Cc: Daniel Vetter <daniel.vetter at ffwll.ch>; David Herrmann
>> > > <dh.herrmann at gmail.com>
>> > > Subject: [Libva] [PATCH] drm: remove va_drm_is_authenticated check
>> > >
>> > > If we do not use a render node we must authenticate.
>> >
>> > It is not true.  A root or master user can access /dev/dri/card0
>> > without authentication in drm.
>> > va_drm_is_authenticated() is used to check for this cases.
>> >
>>
>> Surely you're not suggesting that running your video player as root is
>> a wise idea ;-)
>
>Agreed.

I also agree we should run video player as a normal user, however some customer prefers root.

>
>>
>> Regardless, there's something _really_ fishy with libva if it needs
>> va_drm_is_authenticated.
>> Any other software out there does not need to (or do so) - some
>> examples include Xorg, Wayland and other Weston compositors, Mesa, IGT
>> (a ton of GPU tests) ... be that as root, user or otherwise.
>
>
>We don't need it, in my opinion.

We can still run VAAPI application as root to access /dev/dri/card0 with this patch, but cannot
run 2+ VAAPI applications at the same time.  We can suggest customer to use render node first because
authentication isn't needed for render node.

I am fine to apply the patch.

>
>Sean
>
>>
>> Emil
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