[PATCH -mm 1/2] kexec jump -v12: kexec jump

[Pavel Machek]

On Sat 2008-07-12 11:02:17, Nigel Cunningham wrote:
> Hi.
> 
> On Fri, 2008-07-11 at 16:11 -0400, Vivek Goyal wrote:
> > Hi Andrew,
> > 
> > We can use this patchset for hibernation, but can it be a better way of doing
> > things than what we already have, I don't know. Last time I had raised
> > this question and power people had various views. In the end, Pavel wanted
> > this patchset to be in.  Pavel, can tell more here...
> > 
> > To me this patchset looks interesting for couple of reasons.
> > 
> > - Looks like an interesting feature where one can have a separate kernel
> >   in memory and one can switch between the kernels on the fly. It can
> >   be modified to have more than one kernel in memory at a time.
> 
> I'm not sure how useful that would be, though. I already have
> functionality in TuxOnIce which allows you to resume a different image
> instead of powering off (roughly the same thing when combined with not
> removing the image after resuming). It was neat when testing to be
> able

Beaty of kjump is that it is supposed to used on half-broken system,
so it is useful for debugging.

> > - So far kexec was one directional. One can only kexec to new kernel and
> >   old kernel was gone. Now this patchset makes kexec functionality kind
> >   of bidirectional and this looks like logical extension and can lead
> >   to intersting use cases in future.
> 
> Ah. You mean keeping both kernels in memory at the same time? In the
> above, I was replacing one image with another.

Yep, kjump keeps both kernels loaded at the same time.
									Pavel
-- 
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