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Going back to Debian

Posted on | September 17, 2008 | 2 Comments

This has been a very trying week with Ubuntu.

I recently deployed a large Xen farm using Ubuntu Hardy. Mixing 32 and 64 bit guests under a 64 bit hypervisor with a 64 bit privileged domain exposed some interesting bugs, such as time going backwards when using the default xen clock source. This nasty bug tricked the kernel into thinking a soft lockup happened, when in fact it did not. Great, we already migrated 4 dozen virtual machines that now crash every three hours.

I chimed in on several bug reports .. all of them were closed with “Please see if the Intrepid kernel solves this issue” .. then come to find out .. no Xen dom-0 kernel is even planned for intrepid. I can say, most decidedly, this will not solve my problem :)  Quote  Ubuntu “your on your own for dom-0″.  Lovely. So much for long term support.

Then we find out that Mozilla demanded that Ubuntu make Firefox users accept an end user license agreement, stipulating to trademark protection .. even if the trademark did not apply in their country prior to gaining the privilege to use their free software. The EULA is full of legalese, people that I teach typically speak English as a second language. Most disturbingly, there was no communication from Canonical regarding the EULA, it ‘just appeared’ which caused a major backlash in the Ubuntu community.

No Xen? Forced end user license agreements for stuff that is not in the restricted repository? Sorry, but Ubuntu is just not usable to me in the future in any endeavor. Debian has a much slower release cycle, but that doesn’t mean that I can’t create my own trivial repositories and release more frequently.

Mark Shuttleworth is doing good things, in fact Ubuntu is working diligently to get more drivers freed. Canonical pays lawyers so that we don’t have to .. I respect and admire their work. But I can not rely on Ubuntu for what I have grown accustomed to using it for any longer.

Now I have to fork Hardy just so existing customers can continue to pull in updates to their xen-0 kernels … and so students aren’t confronted with future ‘backdoor’ license agreements that they can not hope to understand. I just don’t trust Canonical any longer.

Et tu, Mozilla?


2 Responses to “Going back to Debian”

  1. RichM
    September 20th, 2008 @ 7:46 am

    Hi Tim,

    Is that the “jiffies” clocksource thing? that always seemed strange to me.

  2. tinkertim
    September 20th, 2008 @ 9:03 am

    @Rich -

    One of them. The clock skew problem isn’t always solved by using jiffies. A bit of jitter is OK, however this particular nasty causes the kernel to believe that a process spent 11 seconds on a given CPU, when in fact it likely finished and exited 10.99999999 seconds prior.

    The other issues include Xen patched kernels not correctly counting (or presenting) all CPUs and a bunch of other stuff.

    Weighing that, plus a hundred other important things that went into .27, plus our need to get the parts of grsecurity that are compatible with Xen into the mix … just screamed ‘fork’.

    Quote Ubuntu : “Your on your own for dom-0, use mainstream Linux + paravirt ops for dom-u’s”. So, were really just following advice by doing it on our own.

    The end result will be , plus all major fixes from 2.6.27, plus CVE patches, plus xen dom-0 operations, plus (optional) grsecurity without PAX. We’re regression testing now and hope to have it out next week.

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