[lkml]   [2007]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [RFC] enhancing the kernel's graphics subsystem
    Dave Airlie wrote:
    > On 5/21/07, Jon Smirl <> wrote:
    >> On Thu, 17 May 2007 14:23:45 -0700, Jesse Barnes wrote:
    >> > In collaboration with the FB guys, we've been working on enhancing the
    >> > kernel's graphics subsystem in an attempt to bring some sanity to the
    >> > Linux graphics world and avoid the situation we have now where several
    >> > kernel and userspace drivers compete for control of graphics devices.
    >> How is supporting different users logged into each head going to work?
    >> The original model for this was to give each head its own fbdev device.
    >> It is important that each user be able to set their own mode without
    >> being
    >> root.
    > TThe problem with that is the concept of heads is flawed... there is
    > in reality no such
    > thing, you have crtcs and outputs, no heads. So any attempt to enforce
    > the head concept involves putting policy into the kernel, as if I have
    > 3 outputs but 2 crtcs how do I decide the mappings without the admin
    > telling the kernel,
    One device per crtc. You can then have two users, running consoles
    or xservers on their crtcs, without having to involve root.

    The crtc->output mapping must still be done by root of course.

    This solution allow the useful case where the computer boots, the boot
    set up a crtc->output mapping. Then users log in through the
    various consoles (using getty or xdm or similiar) using their grahphical
    devices in whatever way they want. A true multiseat setup.

    And if one user needs to use all the screens for multi-display work?
    Let root change the mappings, possibly through some sudo setup.

    Helge Hafting
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    More majordomo info at
    Please read the FAQ at

     \ /
      Last update: 2007-05-21 11:21    [W:0.049 / U:2.764 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site