Bug 82551 - monitor resolution wrongly set when using kernels > 3.13
Summary: monitor resolution wrongly set when using kernels > 3.13
Status: NEW
Alias: None
Product: Drivers
Classification: Unclassified
Component: Video(DRI - non Intel) (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: drivers_video-dri
Depends on:
Reported: 2014-08-17 00:23 UTC by Javier Fernandez
Modified: 2014-09-23 00:45 UTC (History)
2 users (show)

See Also:
Kernel Version: 3.14.x and above
Tree: Mainline
Regression: No


Description Javier Fernandez 2014-08-17 00:23:12 UTC

Im currently an UBuntu user since ages

My problem has started to show when using mainstrean 3.14 kernels. 3.13 ones work  properly (thats what im using as of now, while writing this)

When booting the PC, it seems that the monitor tries to switch to some kind of not-supported resolution. Screen stays blinking in blank forever. I can properly shut down via power button, so system is not frozen.

i upgraded yesterday to Ubuntu Utopic, which server kernel 3.16.x currently, but i cant not use it when booting with 3.16 kernel....
Comment 1 Javier Fernandez 2014-08-17 00:29:09 UTC
oh, i must say, im running kernel 3.16 (Ubuntu Utopic) in 2 laptops with no problems:

1.- AMD Turion II M520 with AMD Radeon HD5145 GPU
2.- AMD A6-5200 with AMD Radeon HD8400

the PC that has problems is a desktop PC

-  Intel Core i3-530 with AMD Radeon HD 6570 PCI-express
Comment 2 Alex Deucher 2014-08-21 16:57:12 UTC
Please attach your xorg log and dmesg output.  Can you bisect?
Comment 3 Javier Fernandez 2014-08-21 18:11:12 UTC
those are in a bug i opened to Canonical Launchpad (im not sure which is the responsible group....)

Comment 4 Javier Fernandez 2014-08-21 18:12:12 UTC
also, this problem only happens using the open source ati driver. It works OK with fglrx
Comment 5 Alex Deucher 2014-08-21 19:23:32 UTC
If it works with 3.13 can you use git to bisect what change between 3.13 and 3.14 caused the regression?
Comment 6 Javier Fernandez 2014-08-21 21:25:29 UTC
ugh... i dont have enough skills for playing with kernel :S
Comment 7 Javier Fernandez 2014-09-10 22:16:00 UTC
Hello again,

i have been able to boot correctly with the open source driver using the Ubuntu specific kernel 3.16.0-14-lowlatency

should i try with upstream 3.16.2 ?
Comment 8 Alex Deucher 2014-09-10 22:19:19 UTC
to be clear, are you saying that it's working again with 3.16?  E.g.,

3.13 -> works
3.14 -> doesn't work
3.16 -> works
Comment 9 Javier Fernandez 2014-09-11 02:28:51 UTC
well, actually i havent tested upstream versions of 3.16 kernels, only Ubuntu kernels (which are patched)

thats why i ask about installing upstream ones...

what do u think?

Also, i can remember earlier releases of 3.16 kernels on which radeon open source driver didnt work ( 3.16.0-8)

3.13 -> works
3.14 -> doesn't work
3.15 -> doesn't work
3.16 -> works

seems so, yes
Comment 10 Javier Fernandez 2014-09-11 02:29:51 UTC
the kernel i am using now and on which open  source driver is working is 3.16.0-14-lowlatency
Comment 11 Alex Deucher 2014-09-11 13:04:14 UTC
You'll have to ask ubuntu if they have added any special changes.  I'm not able to reproduce any display problems.
Comment 12 Javier Fernandez 2014-09-23 00:45:19 UTC

I´been away from home (holydays), today i have come back, and when booting PC..... again same problems.

I was using 3.16.0-14-lowlatency

i then upgraded to 3.16.0-16-lowlatency, with no success.

I had to install fglrx again

So no, its *not* working with 3.16 .... in my PC

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