Re: [Bisected] Output to external monitor is broken (Re: Linux2.6.31-rc9)

From: Linus Torvalds
Date: Mon Sep 07 2009 - 14:37:49 EST

[ Just adding all the right people to the email participants line.
Eric, Jesse, Zhao, Ma Ling - should I just revert that commit?

Carlos - can you also do the full dmesg _with_ the corruption? I realize
that your screen is unreadable, but if you can just log in blindly, and
do a "dmesg > saved-dmesg-file" and then do a clean reboot? No need for
a serial console or anything fancy - I assume the machine is still
working, just with bad output.

It might also be a good idea to boot with "drm.debug=15" to enable much
more debugging output.
- Linus ]

On Sun, 6 Sep 2009, Carlos R. Mafra wrote:
> On Sat 5.Sep'09 at 16:54:27 -0700, Linus Torvalds wrote:
> > Go wild, and please give this a final round of testing.
> The output from my Vaio laptop to the external monitor (LG Flatron M228WD)
> is broken now. The screen is all messed-up once the boot messages from the
> kernel appear on it (see the picture at the link below).
> I bisected it down to f8aed700c6ec46ddade6570004ce25332283b306 ("drm/i915:
> Set crtc/clone mask in different output devices"). I doubled checked
> that reverting this commit from 2.6.31-rc9 fixes the problem.
> The picture of the bad output is here:
> as well as my config:
> and dmesg (with the above commit reverted):
> (the vga=0x0364 in the command line does not work since I
> enabled KMS, so I get a prompt in the beginning from which I
> choose vga=0. But the above regression is not affected by this
> choice because the command line was always the same during
> bisection)
> If there is anything else I can do, just let me know.
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