Re: [PATCH] x86_64 kexec: Remove experimental mark of kexec

[ebiederm@xmission.com (Eric W. Biederman)]

Piet Delaney <piet@bluelane.com> writes:

> On Wed, 2006-09-06 at 21:22 +0200, Andi Kleen wrote:
>> On Wednesday 06 September 2006 18:55, Eric W. Biederman wrote:
>> > 
>> > kexec has been marked experimental for a year now and all
>> > of the serious problems have been worked through.  So it
>> > is time (if not past time) to remove the experimental mark.
>> > 
>> 
>> Hmm, I personally have some doubts it is really not experimental
>> (not because of the kexec code itself, but because of all the other drivers
>> that still break)
>
> What drivers does kexec break?

Kexec doesn't break any drivers.  kexec exposes bugs in driver initialization
handling, when drivers on not robust.

The normal kexec case should be quite simple to handle and because we cleanup
just like a reboot, the difference is that we don't ask the BIOS to reset us
first.

The kexec on panic case is painful, because drivers in the original kernel are
not stopped or shutdown, and so the secondary kernel gets to initialize drivers
from an essentially random state.

Eric