On Wed, 2015-07-08 at 17:10 +0100, Emil Velikov wrote: > On 8 July 2015 at 14:55, Alex Deucher <alexdeucher at gmail.com> wrote: > > On Wed, Jul 8, 2015 at 9:53 AM, Steven Newbury < > > steve at snewbury.org.uk> wrote: > > > > > > > > > On Wed Jul 8 14:20:28 2015 GMT+0100, Alex Deucher wrote: > > > > On Wed, Jul 8, 2015 at 8:58 AM, Steven Newbury < > > > > steve at snewbury.org.uk> wrote: > > > > > > > > > > > > > > > On Tue Jul 7 15:12:28 2015 GMT+0100, Alex Deucher wrote: > > > > > > On Tue, Jul 7, 2015 at 9:46 AM, Steven Newbury < > > > > > > steve at snewbury.org.uk> wrote: > > > > > > > > > > > > > > I've tried an xserver-1.16, and ddx, libdrm without LTO > > > > > > > and with > > > > > > > gcc4.9. Exactly the same thing. I wondered whether the > > > > > > > unused i810 > > > > > > > could be interfering but triggering a device "remove" > > > > > > > before starting > > > > > > > X made no difference. > > > > > > > > > > > > > > I'm a bit of a loss. I suppose I could try writing a > > > > > > > simple test for > > > > > > > drmSetInterfaceVersion(). At least that should > > > > > > > determine whether the > > > > > > > xserver/ddx is in the clear. > > > > > > > > > > > > > > Any other ideas? > > > > > > > > > > > > > > > > > > > Can you start a non-X runlevel and start X manually as > > > > > > root (assuming > > > > > > you are using a login manager now)? > > > > > > > > > > > My test program worked fine. I considerably improved it over > > > > > the version I posted. I'll send it to the list when I get > > > > > back. > > > > > > > > > > I removed the drmSetInterfaceVersion() from radeon_kms.c and > > > > > it got much further. Starting Xserver as root apparently > > > > > started normally, according to the log, although there was > > > > > a permission denied error on mode set during init. I don't > > > > > know whether it was related or not, but the display then > > > > > hung with a non-blinking cursor. Strange to get a permission > > > > > denied as root! > > > > > > > > > > Starting GNOME via gdm gives a working slow X session but > > > > > for some reason only uses sw dri even though the Xorg log > > > > > shows r200 DRI2 as initialized. Perhaps it's a config error > > > > > somewhere.. ? > > > > > > > > > > startx as a regular user just works! > > > > > > > > > > But mutter doesn't, perhaps that's > > > > > why a gnome session isn't working. It just gives the > > > > > following error: > > > > > Cogl-ERROR **: Failed to create texture 2d due to > > > > > size/format constraints > > > > > > > > > > Mutter is supposed to work on r200, right? > > > > > > > > IIRC it tries to use a render buffer format that's not > > > > supported by the hw. > > > Is there anything to be done about it? Have to use a different > > > wm/compositor? > > > > > > > Another wm or compositor may help. > > > > > Any idea why removing the call from radeon_kms.c worked? > > > > No idea. > > > From a quick look at the actual implementation drmSetInterfaceVersion > is not something that we want/need to use with KMS drivers. > > In general the original issue sound like the drm driver is not > (fully) > loaded before the xserver/ddx kicks in. Additionally it may be a race > condition if something else (plymouth) is using the device. In the > latter case DRM_MASTER might still be held by $(other_app), thus > attempting to either SetInterfaceVersion or do any modeset operation > will fail. > > Sitting on a KMS console, "systemctl start gdm", no plymouth installed. It's just during Xserver initialisation that drmSetInterfaceVersion() fails. AFAIK Xserver startup is entirely single process, single thread. I've written a little test utility which works fine on the system in question.
Compile attached file with: gcc -O2 -o test-drm test-drm.c $(pkg-config --cflags libdrm) $(pkg -config --libs libdrm) > Personally I would add a healthy amount of printk/printf though the > kernel drm + radeon and the ddx. I guess it doesn't really matter since patching out the code "fixes" it... -------------- next part -------------- A non-text attachment was scrubbed... Name: test-drm.c Type: text/x-csrc Size: 1783 bytes Desc: not available URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20150708/f4f234fa/attachment-0001.c> -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 181 bytes Desc: This is a digitally signed message part URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20150708/f4f234fa/attachment-0001.sig>
