Re: [PATCH] x86/kexec: Fix crash on transition to a 32bit kernel on AMD hardware

[Ian Jackson <iwj@xxxxxxxxxxxxxx>]

Andrew Cooper writes ("Re: [PATCH] x86/kexec: Fix crash on transition to a 
32bit kernel on AMD hardware"):
> On 01/11/2021 12:13, Ian Jackson wrote:
> > Andrew Cooper writes ("Re: [PATCH] x86/kexec: Fix crash on transition to a 
> > 32bit kernel on AMD hardware"):
> >> This path is only taken for a 32bit crash kernel.  It is not taken for
> >> 64bit crash kernels, or they wouldn't work on AMD either, and this is
> >> something we test routinely in XenServer.
> >>
> >> The worst that can happen is that I've messed the lretq pattern up, and
> >> broken transition to all 32bit crash kernels, irrespective of hardware
> >> vendor.
> >>
> >> It will either function correctly, or explode.  If it is broken, it
> >> won't be subtle, or dependent on the phase of the moon/etc.
> > Thanks for this confirmation.
> >
> > Release-Acked-by: Ian Jackson <iwj@xxxxxxxxxxxxxx>
> 
> Thanks.
> 
> Unfortunately, I've made a blunder here.  The code as implemented is
> broken on Intel, and works on AMD.  (I.e. I need to swap Intel and AMD
> in the commit message).  Have done locally, but won't repost just for that.

OK, thanks.

Ian.