[Mesa-dev] [PATCH 1/3] egl/x11_dri3: disable WL_bind_wayland_display for devices without render nodes

[Frank Binns]

On 20/06/16 10:48, Michel Dänzer wrote:
> On 18.06.2016 02:41, Frank Binns wrote:
>> Up until now, DRI3 was only used for devices that have render nodes, unless
>> overridden via an environment variable, with it falling back to DRI2 otherwise.
>> This limitation was there in order to support WL_bind_wayland_display as it
>> requires client opened device node fds to be authenticated, which isn't possible
>> when using DRI3. This is an unfortunate compromise as DRI3 provides security
>> benefits over DRI2.
> What exactly is it that works with render nodes but not with
> unauthenticated non-render nodes? Isn't that a kernel bug?
>

The problem isn't that something doesn't work with unauthenticated
non-render nodes (wouldn't that be the kernel bug?) but that if a
client opens the primary/legacy node it needs the resulting fd to
be authenticated, which isn't supported by the X11 DRI3 protocol.