Bug#783705: xserver-xorg-video-radeon: Weird X wakeup problem since Jessie upgrade

[Alex Deucher]

On Wed, Apr 29, 2015 at 7:45 AM, Steve McIntyre <steve at einval.com> wrote:
> Package: xserver-xorg-video-radeon
> Version: 1:7.5.0-1
> Severity: normal
>
> Hi folks,
>
> I upgrade my main office desktop to Jessie on Monday, and just about
> evrrything worked really well - just half a dozen oro so config files
> needed merging with new upstream etc. Painless!
>
> However, I'm now seeing a really odd problem with X on my
> machine. I've got an AMD graphics card, which Xorg.0.log tells me is a
>
>  RADEON(0): Chipset: "PITCAIRN" (ChipID = 0x6810)
>
> and a DP+ connection to a lovely 27" NEC monitor. It works just fine
> when I'm using it, *but* when I leave it overnight and come in the
> next morning it doesn't want to wake up properly. I'm locking the
> screen with Xscreensaver and then turning off the monitor as I leave.
>
> In the morning, I turn on the screen and I don't get a display at
> all. I've wiggled the mouse, hit numlock on the keybard (the numlock
> led illuminates fine), etc., but no display. I've seen this kind of
> thing happen in the past on some machines, so I switch to VT1 and back
> to see if that helps. Still no display at all, either on console or
> under X. I log in remotely and I can see that the Xorg.0.log file has
> been updated with mode lines for the monitor, suggesting things have
> just woken up fine. But still no display.
>
> Here's the really weird thing: at this point, the monitor has
> basically locked up. It won't respond to the power/input/menu butttons
> at all, and is still showing the blue LED that says "I have signal"
> rather than switching to the amber "no signal" warning. Therefore, I
> can only assume there's a problem here with some weird invalid DP
> signal being produced.
>
> Yesterday, I gave up and rebooted after a few minutes - I had work to
> do. Today, I started searching for any other reports like this using
> my laptop. About ten minutes later while I was doing this
> (approximately, wasn't paying massive attention at this point), my
> desktop screen suddenly came to life and now it's working OK.
>
> I have no idea of where to even start debugging this. Help!
>


If this is a regression, what previous version was working correctly?
Does the problem only happen when you physically power off the
monitor?  Does it come back ok when you let dpms kick in?  How about
when you physically disconnect the monitor from the computer?  Also,
what screensavers are you using?  There may be a problematic GL
screensaver that's causing a GPU lockup.  Can you try forcing a single
known stable screensaver?

Alex