Fresh install with glib-2.6.1 masked from the beginning

noisebleed

Hi.

My Gentoo system is currently running with glibc-2.6.1 but because of a nasty problem related to my Via C7 processor it is freezing very often. The only way to keep the system healthy is to downgrade glibc.

So, I went to do a fresh install but the stage3 already has glibc-2.6.1 and I can't get to downgrade to 2.5-r4.

Is there any way to do this? Stage1 helps? Is there any documentation about it?

Help would be much appreciated. Thanks.

kevstar31 · Guru Joined: 22 Nov 2006 Posts: 449 Location: Ohio

You could try using catalyst to create you own tarball. Use a tarball of your current system to make a seed stage.
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noisebleed · Posted: Sun Nov 30, 2008 3:13 pm Post subject:

Hi kevstar31. Thanks for the reply.

In which way using catalyst can give me a glibc install previous to 2.6.1?

Note: I don't mind loosing my current install. I just need a new one with glibc < 2.6.1

cyrillic · Posted: Sun Nov 30, 2008 3:56 pm Post subject:

If you start with an older stage tarball, then you will get an older glibc.

I am not sure how far back they go, but if an old enough stage tarball is not available, then what kevstar31 suggested is probably the way to go.

noisebleed · Posted: Sun Nov 30, 2008 4:09 pm Post subject:

Hi cyrillic.

I will search for an old hardened stage (I'm using/want to use an hardened system). I've downloaded from barfoo.org but all of the available stages are from this year.

Would stage1 help? Can I select which glibc version to build using this method?

About catalyst I'm not sure if I have understood the method. How can I get glibc-2.5 from there?

I was trying Method B of the gentoo-wiki howto "Downgrade Glibc" but portage stills don't allow me to downgrade.
Howto available at: http://74.125.77.132/search?q=cache:a5wUwhrWHMEJ:test.gentoo-wiki.com/Downgrade_Glibc+gentoo+glibc+downgrade&hl=pt-PT&ct=clnk&cd=7&gl=pt (cached by google)

zyko · Posted: Sun Nov 30, 2008 7:03 pm Post subject:

You can create your own "stage3 tarball" without any additional tools. Portage has an environment variable named ROOT (see man emerge). You can make a directory like /home/my_new_gentoo and then emerge the system set of packages into that directory via

Captain Newbie · Apprentice Joined: 22 Dec 2006 Posts: 182 Location: Socal

Method C at the linked page above is insane - don't try it.

Method B fails because the 2.5-r4 glibc ebuild tries to save you from yourself ("Downgrading glibc is NOT supported...destruction"). (Properly, I might add.) You could try to step around this by manually editing the ebuild and rebuilding its digest, but that's frightening. The catalyst approach sounds better.

Catalyst is the Gentoo Release Engineering tool that you can use to create custom stages. I'm not certain (never had a problem with new glibc), but I suspect that you can create a custom Stage 3 tarball with your desired version of glibc by using Catalyst, and masking the appropriate versions of glibc in portage_confdir/package.mask, then running Catalyst to generate your customized, tailor-made stage. (Then unpack that stage, etc. etc.)

Make sure you back up /etc and /var/lib/portage/world - you will want to save your configuration files and world file, which unpacking a stage tarball will happily blow away.

You'll need to use Catalyst to create a Portage snapshot first, then edit your .specfile to your needs (subarch, target, snapshot, CHOST, CFLAGS), as well as package.mask in portage_confdir to mask new versions of glibc.

I like the idea of using Catalyst far more than the methods linked above - but that's just me.

edit: or what Zyko said.
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noisebleed · Posted: Sun Nov 30, 2008 7:12 pm Post subject:

Hi Captain Newbie. Thanks for the explanation.

Indeed Catalyst sounds like a good option. But, right now, I'm installing my system based on an old (2007) hardened stage3 found on http://darkstar.ist.utl.pt/gentoo/experimental/x86/hardened/stages/stage3-x86-hardened-2007.0_pre20070209.tar.bz2. Glibc version included is lower than 2.6.1 so it looks good. There was no 686 stage so I'm CHOSTing from 386 now

If this process fails I will take a look at Catalyst and maybe ask some more questions

The adventure continues...

noisebleed · Posted: Sun Nov 30, 2008 7:14 pm Post subject:

Oh, I missed your reply zyko. Thanks for the "ROOT feature" info