modeset(0): drmSetMaster failed: Permission denied

[Russ Whitaker]

On Mon, 1 May 2017, YuGiOhJCJ Mailing-List wrote:

> Hello,
>
> I have built xorg-server, xauth, and xinit with their dependencies.
> When I do startx I get "xf86OpenConsole: Cannot open virtual console 7 (Permission denied)".
> So, I change the permissions on /dev/tty7 to 660.
> Now, when I do startx I get "modeset(0): drmSetMaster failed: Permission denied".
>
> I read in the web that some people use SUID on /usr/bin/Xorg to solve this problem but I am not sure if it is safe to do that and maybe there is a better way.
> Same thing for my permissions on /dev/tty7, I would prefer to not change permissions if possible.
> With the Xorg provided by my distro, there is no SUID on /usr/bin/Xorg and only 0620 on /dev/tty7 which is better, and it works fine.
> So, I am wondering why it does not work with my own Xorg.
>
> Any idea please?

Set permissions to 755

>
> Thank you.
> Best regards.
>
> ---
>
> Distro: Slackware64 14.2
> Kernel: Linux 4.9.24
> Built and installed packages:
> -bigreqsproto-1.1.2
> -compositeproto-0.4.2
> -damageproto-1.2.1
> -dri2proto-2.8
> -dri3proto-1.0
> -fixesproto-5.0
> -fontsproto-2.1.3
> -glproto-1.4.17
> -inputproto-2.3.2
> -kbproto-1.0.7
> -libdrm-2.4.80
> -libepoxy-1.4.1
> -libfontenc-1.1.3
> -libICE-1.0.9
> -libpciaccess-0.13.5
> -libpthread-stubs-0.1
> -libSM-1.2.2
> -libvdpau-1.1.1
> -libX11-1.6.5
> -libXau-1.0.8
> -libxcb-1.12
> -libXdamage-1.1.4
> -libXext-1.3.3
> -libXfixes-5.0.3
> -libXfont2-2.0.1
> -libxkbfile-1.0.9
> -libXmu-1.1.2
> -libxshmfence-1.2
> -libXt-1.1.5
> -mesa-17.0.4
> -mesa-demos-8.3.0
> -pixman-0.34.0
> -presentproto-1.1
> -randrproto-1.5.0
> -recordproto-1.14.2
> -renderproto-0.11.1
> -resourceproto-1.2.0
> -scrnsaverproto-1.2.2
> -videoproto-2.3.3
> -xauth-1.0.10
> -xcb-proto-1.12
> -xcmiscproto-1.2.2
> -xextproto-7.3.0
> -xf86driproto-2.1.1
> -xineramaproto-1.2.1
> -xinit-1.3.4
> -xorg-server-1.19.3
> -xproto-7.0.31
> -xtrans-1.3.5
> _______________________________________________
> xorg at lists.x.org: X.Org support
> Archives: http://lists.freedesktop.org/archives/xorg
> Info: https://lists.x.org/mailman/listinfo/xorg
> Your subscription address: %(user_address)s
>