Re: [BUG BISECTED FAILED] Phenom microcode revision mis-identified

From: Gene Heskett
Date: Sun Dec 29 2013 - 15:17:32 EST

On Sunday 29 December 2013, Gene Heskett wrote:
>On Sunday 29 December 2013, Jason Cooper wrote:
>>On Sun, Dec 29, 2013 at 12:47:02PM -0500, Gene Heskett wrote:
>>> On Sunday 29 December 2013, Gene Heskett wrote:
>>> >Resend, incorrect subject line
>>> >
>>> >Here is the copy/paste of the final git bisect bad report:
>>> >
>>> >First, the reason for the bisect:
>>> >gene@coyote:~/linux-stable$ dmesg | grep -A2 microcode
>>> >[ 0.518304] microcode: CPU0: patch_level=0x01000065
>>> >[ 0.518396] microcode: CPU1: patch_level=0x01000065
>>> >[ 0.518498] microcode: CPU2: patch_level=0x01000065
>>> >[ 0.518593] microcode: CPU3: patch_level=0x01000065
>>> >[ 0.518745] microcode: Microcode Update Driver: v2.00
>>> ><tigran@xxxxxxxxxxxxxxxxxxxx>, Peter Oruba
>>> >
>>> >The output above should have in each cpu case, a second, or final
>>> >line showing a patch level 0x0100083 in all cases.
>>> >This failure is on an AMD phenom 9550 equipt machine.
>>> >
>>> >I can and have built from the tarball pull, a 3.8.2 which does work
>>> >correctly. The tarball build of 3.8.3 fails as above, and a tarball
>>> >build of 3.12.6 still fails.
>>> >
>>> >gene@coyote:~/linux-stable$ git bisect bad
>>> >908e88f285b909011dc7dbce5abaacf123f2f68d is the first bad commit
>>> >commit 908e88f285b909011dc7dbce5abaacf123f2f68d
>>> >Author: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
>>> >Date: Mon Feb 25 16:09:12 2013 +0000
>>> >
>>> >I'll next do a "git checkout v3.8.2" to double check that it works.
>>Please re-read the manpage for git bisect, particularly the section
>>"Basic bisect commands". You need to keep repeating building and
>>booting the kernel, execute 'git bisect [good|bad]', as git bisect
>>checks out different commits to try. Depending on the number of
>>commits, it can take 7 to 10 iterations before it nails it down to the
>>bad commit.
>>$ git log --oneline v3.8.2..v3.8.3 | wc -l
>>So you started at v3.8.3, said v3.8.2 is good. git bisect will then
>>checkout a commit in the middle (of the 103 commits to choose from).
>>You need to build that kernel, boot it, and see if the error occurs.
>>Then, type 'git bisect [bad|good]' depending on what happened. When
>>that command returns, it has checked out a different commit between
>>v3.8.2 and v3.8.3. Build, boot, and run 'git bisect [good|bad]'
>>depending on if the patch_level was reported properly. Repeat until it
>>reports nothing left to test.
>>> FWIW, a git checkout v3.8.2 also fails, so next I'll move my working
>>> tarball build .configs into that tree & see if it works.
>>If the config you started with worked for v3.8.2 and didn't for v3.8.3,
>>keep using it.
>>> This is getting stranger, a checkout v3.8.2 is supposed to match the
>>> tarball I got from isn't it?
>>Yes, see above. As soon as you started the bisection process, you were
>>no longer on version 3.8.2 or 3.8.3, but somewhere in between. That's
>>what's supposed to happen.
>>Once you run enough iterations to get nothing left to test, record the
>>commit it identified, and run 'git bisect reset'.
>I did do that, the above report was the final of about 8 or 9 reboots
>after telling it each time "git bisect bad".
>And that "reset" is what I did not do just now. Instead, I went directly
>to git checkout v3.8.2, then moved a known good pair of configs (which
>now give me no option to build the 64 bit kernel as the first line in a
>make xconfig)
>Then, because it was still building a bunch of stuff that aren't
>applicable to my hardware, so I stripped several pages worth of modules,
>and a new 3.8.2 from linux-stable is building now. But it will take 20
>minutes longer. If this doesn't work, then I'll copy these .configs
>back to that tarball tree and try that. One things is for sure, I'm
>keeping my coffee warm on that phenom. ;-)
>If it then works for the tarball built kernel, then I'll do the git
>bisect reset and restart, doing the bisect all over again. But this
>time I'll start it at a checkout v3.8.2, git bisect good (if it works
>now) and go toward v3.8.3 bad.
>These will all be 32 bit PAE kernels though as I don't know how to
>convert it to 64 bit when a make xconfig doesn't give me that option.
>Thanks Jason.

Ok, next reboot to 3.8.2, built from linux-stable, checkout v3.8.2, using
the .config files from my tarball built 3.8.2 which works:
gene@coyote:~/src/linux-3.12.0$ dmesg|grep -A2 microcode
microcode: CPU0: patch_level=0x01000065
microcode: CPU0: new patch_level=0x01000083
microcode: CPU1: patch_level=0x01000065
microcode: CPU1: new patch_level=0x01000083
microcode: CPU2: patch_level=0x01000065
microcode: CPU2: new patch_level=0x01000083
microcode: CPU3: patch_level=0x01000065
microcode: CPU3: new patch_level=0x01000083
microcode: Microcode Update Driver: v2.00 <tigran@xxxxxxxxxxxxxxxxxxxx>,
Peter Oruba

So this works, leaving something in the much smaller x86_64defconfig as the
culprit, So now to the bisect reset and restart the bisect moving forward.
More later I expect.

Thanks and Cheers, Gene
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