[Intel-gfx] Revert "sna: Coldplug unknown connections as well"

[Chris Wilson]

On Tue, Sep 22, 2015 at 10:46:09AM +0200, Sedat Dilek wrote:
> On Mon, Sep 21, 2015 at 2:52 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > On Mon, Sep 21, 2015 at 02:48:03PM +0200, Sedat Dilek wrote:
> >> On Mon, Sep 21, 2015 at 11:42 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> >> > On Sun, Sep 20, 2015 at 08:20:21PM +0200, Sedat Dilek wrote:
> >> >> Hi,
> >> >>
> >> >> I am here on Ubuntu/precise AMD64 with libdrm v2.4.65 and mesa v10.6.8.
> >> >>
> >> >> I cannot see my LightDM login-manager, my system hangs in VT-1.
> >> >>
> >> >> When I revert...
> >> >>
> >> >> commit 650da13c7257019728cfca361dfcbe34a6c526ef
> >> >> "sna: Coldplug unknown connections as well"
> >> >
> >> > All it is doing is a RRGetInfo() call after 2 seconds if the display
> >> > manager hasn't already done so. Easiest step forward is to look at the
> >> > ddx logs to see timings on who calls what and then try and get the
> >> > lightdm + unity logs to see why they changed behaviour.
> >> >
> >>
> >> Yes, I can look at the LightDM and Unity logs.
> >> Shall I build my intelddx with debugging enabled?
> >
> > The only thing of interest will be the timings given by the full debug
> > log. I don't expect to see a problem as such, but could be proven wrong.
> >
> >> >> ...everything is as usual.
> >> >
> >> > Apart from the kernel issue...
> >> >
> >>
> >> Which kernel-issue?
> >>
> >> On shutdown and after LightDM closes, my system hangs 4ever in VT-1,
> >> so reverting above commit does not really help.
> >
> > That ^ strongly suggests an issue lower down the stack.
> >
> 
> I have built my intelddx via...
> 
> $ ./configure --prefix=/opt/xorg --disable-dri1 --enable-dri2
> --disable-dri3 --disable-tear-free --enable-debug=full
> 
> ...(for more see my config.log).
> 
> And added the following boot-params to the 3.13.y-Ubuntu-kernel command-line...
> 
> Command line: BOOT_IMAGE=/boot/vmlinuz-3.13.0-64-generic
> root=UUID=001AADA61AAD9964 loop=/ubuntu/disks/root.disk ro drm.debug=7
> log_buf_len=4M
> 
> ...(for more see kern-log.txt and syslog.txt).
> 
> My libdrm is v2.6.56 and mesa is v10.6.8 (for more see Xorg log).
> 
> SNA ColdPlug seems to be activated...
> 
> [    32.436] sna_mode_coldplug()
> 
> No sure where to look for LightDM and Unity logs.

/var/log/lightdm/:0*

Not sure where unity ends up.

> Hope this helps.

It did,

commit 31d42ed5637a1b2223d48d0db4d7c512b27aee07
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Tue Sep 22 10:23:24 2015 +0100

    sna: Check for udev events before reading
    
    When performing RRGetInfo() we drain any pending uevents before checking
    the CRTC/connector statuses. However, some versions of libudev do a
    blocking read and so when we call RRGetInfo() from a Timer callback
    (outside of the usual sigtimer interrupts) that blocking read lasts
    indefinitely.
    
    Reported-by: Sedat Dilek <sedat.dilek at gmail.com>
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Thanks,
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre