On Fri, Sep 26, 2014 at 11:58 AM, Josh Boyer
<jwboyer(a)fedoraproject.org> wrote:
> On Fri, Sep 26, 2014 at 2:53 PM, Andrew Lutomirski <luto(a)mit.edu> wrote:
>> On Fri, Sep 26, 2014 at 11:37 AM, Hans de Goede <hdegoede(a)redhat.com>
wrote:
>>> Hi All,
>>>
>>> Just spend some time debugging this and thought I should share this, see:
>>>
>>>
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=762195
>>>
>>> for details, I've filed a bug to track fixing this in Fedora:
>>>
>>>
https://bugzilla.redhat.com/show_bug.cgi?id=1147062
>>>
>>> There are 2 ways this problem shows itself:
>>>
>>> 1) If using an initrd which has been generated with the troublesome
microcode
>>> update into it, things may already crash during the initrd, e.g. in my case
>>> some luks volumes would not unlock because of this
>>>
>>> 2) When booting an older kernel (and thus an older initrd) things start
crashing
>>> (mostly systemd* processes, grinding everything to a halt) as soon as udev
>>> from the rootfs loads the microcode update
>>>
>>> 2. often will still get you to an emergency shell, at which point one can
>>> create a /etc/modprobe.conf.d/no_microcode.conf file with:
>>>
>>> blacklist microcode
>>>
>>> In there to work around the problem, then regenerate the initrds for newer
>>> kernels, and you should be good to go until bug 1147062 gets fixed properly.
>>
>> Yeah, sorry, I should have tried to notify the right Fedora people in advance.
>
> I knew about it. This is basically a breakdown in communication
> between the kernel people and the microcode_ctl owner. it was
> compounded by the fact that I didn't realize our main dracut
> maintainer was on PTO so I didn't fix dracut myself until this
> morning.
>
>> This is a nasty issue, and no one knows how to solve it for real yet.
>> See this long thread:
>>
>>
http://thread.gmane.org/gmane.linux.kernel/1790211
>
> Yeah. FWIW, I just filed an update to have Fedora use early microcode
> by default. A COPR of this was tested successfully by a few people
> that had the Haswell issue.
>
>
https://admin.fedoraproject.org/updates/dracut-038-29.git20140903.fc21,ke...
Everyone will still crash their system once, though, unless
microcode_ctl learns to blacklist this particular update.
The microcode_ctl package that added this update was karma'd out. So
it shouldn't be in updates-testing any longer, which will help
mitigate how wide spread it is.
Also "Everyone" here is "everyone with a Haswell CPU that has HLE
enabled and managed to get microcode_ctl-2.1-8 from updates-testing in
the window it was available", which fortunately is not anywhere near
"everyone in Fedora". Please use care when throwing around
generalities.
josh