Re: help with git bisecting a bug 16376: random - possibly Radeon DRM KMS related - freezes

From: Martin Steigerwald <Martin@lichtvoll.de>
To: Ken Moffat <zarniwhoop@ntlworld.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: help with git bisecting a bug 16376: random - possibly Radeon DRM KMS related - freezes
Date: Wed, 1 Sep 2010 18:10:24 +0200	[thread overview]
Message-ID: <201009011810.31642.Martin@lichtvoll.de> (raw)
In-Reply-To: <20100831223921.GA23476@deepthought>

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Am Mittwoch 01 September 2010 schrieb Ken Moffat:
> On Tue, Aug 31, 2010 at 09:53:43PM +0200, Martin Steigerwald wrote:
> > Hi!
> > 
> > I am seeking help with encircling the cause of:
> > 
> > [Bug 16376] random - possibly Radeon DRM KMS related - freezes
> > https://bugzilla.kernel.org/show_bug.cgi?id=16376
> > 
> > I started a bisection as described in which has been painful for me -
> > at least for a first time bisection -, but after the second skip of
> > a non- booting kernel git points me to a kernel that is outside of
> > the initial range between good and back.
> > 
> > good is: [60b341b778cc2929df16c0a504c91621b3c6a4ad] Linux 2.6.33
> > 
> > bad is: bad: [64ba9926759792cf7b95f823402e2781edd1b5d4] Merge branch
> > 'for- linus' of git://git.open-osd.org/linux-open-osd
> > 
> > After skipping the last non booting kernel, git bisect put me to
> > 5be796f0b842c5852d7397a82f8ebd6be8451872 which is just 300 lines
> > after 2.6.33-rc2.
> > 
> > Obviously I am not interested in kernels prior 2.6.33. Should I just
> > do a "git bisect good" without trying the kernel or is there some
> > other remedy? its 11 cycles already without testing anything outside
> > the initial good/bad range and it takes about half a day to be
> > somewhat sure that a kernel is good, so I'd like to avoid testing
> > versions outside this range.
> 
>  While you are bisecting, don't believe the version in Makefile.  I
> got similarly freaked out a couple of years ago - if I understood
> correctly, it's something to do with when a change was created.
> 
>  The key point is that during bisection the apparent version *can*
> go back to a version that appears to be before the initial "good"
> kernel.

I verified the version by running git log after doing the skip. And it was 
just 300 lines after Linus commited 2.6.33-rc2. Can git log be showing 
incorrect results during a bisect?

Thanks,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7

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