Bugzilla – Bug 27589
[GM45] Occasional flickering unless powersave=0 is used on lenovo laptops.
Last modified: 2011-01-31 10:14:48 UTC
Created attachment 34894 [details]
dmesg with drm.debug=0x04
Forwarding this bug from Ubuntu reporter Chris Jones:
Flickering screen with lenovo x301 occasionally, limited to the bottom 1/3rd to 1/2 of the screen. Additional reports of the same symptoms on lenovo x200s, G550, and T500. Booting with i915.powersave=0 fixes it for all reporters. When an external monitor is attached the flickering on the LVDS does not occur.
DistroRelease: Ubuntu 10.04
Kernel: Ubuntu 2.6.32-19.28-generic 126.96.36.199+drm33.1
Macine: Lenovo x301, Lenovo x200s, Lenovo T500, Lenovo G550
00:02.0 VGA compatible controller : Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
Subsystem: Lenovo Device [17aa:2114]
Created attachment 34895 [details]
Created attachment 34896 [details]
An update after more comments on the launchpad bug, it seems to be affecting a great deal of other laptops all containing the 8086:2a42 device and not just lenovo ones.
Does this also occur in 2.6.34? I've never seen this on my x200, but I don't discount the possibility of an FBC bug as the lp reports indicate...
Come to think of it, I haven't see the flicker on my x201s for a couple of months...
And the reporters have gone silent. I guess this one is fixed.
As most users have been following the Launchpad bug tracking system, we did not see your last message.
Obviously if you look at the Launchpad bug, reporters are not silent.
The bug is still here, and unless something has been done, this is not solved.
I'm just changing the status back to open just to be sure that someone will pass by here. If a change that actually solved the problem has been done (but not propagated yet to my Ubuntu installation), pardon me for my bold change. But I think this need clarification.
I can confirm it's not yet fixed. I was able to reproduce it with 2.6.32, 2.6.34, 2.6.35 and 2.6.36 in Debian. The BTS entry contains more informations about my setup (it's a Dell Vostro 1014, 8086:2a42):
Please let me know of any information I could provide to help squash this bug.
I've not seen this on my x201s in the last year...
However, I've applied a fix first spotted for Ironlake to the g4x watermark on drm-intel-next:
Author: Chris Wilson <firstname.lastname@example.org>
Date: Wed Jan 19 15:04:42 2011 +0000
drm/i915: Include TLB miss latency in g4x watermark computations
Reports of FIFO underruns are still persisting on gm45.
Signed-off-by: Chris Wilson <email@example.com>
(In reply to comment #8)
> I can confirm it's not yet fixed. I was able to reproduce it with 2.6.32,
> 2.6.34, 2.6.35 and 2.6.36 in Debian. The BTS entry contains more informations
> about my setup (it's a Dell Vostro 1014, 8086:2a42):
I can no longer reproduce this issue with 2.6.37, as commented in the downstream report. Whatever got into 2.6.37 (intentionally or not) seems to have fix it. :-)
I can still reproduce it on 2.6.36 consistently.
Great, thanks for the update.