Re: FAILED: patch "[PATCH] x86/sev: Make the #VC exception stacks part of the default" failed to apply to 5.15-stable tree

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Nov 16, 2021 at 12:52:44PM +0100, Borislav Petkov wrote:
> On Tue, Nov 16, 2021 at 12:24:01PM +0100, Greg KH wrote:
> > Nope, planning ahead:
> > 	$ ~/linux/stable/commit_tree/id_found_in 7fae4c24a2b8
> > 	5.16-rc1 queue-4.4 queue-4.9 queue-4.14 queue-4.19 queue-5.4 queue-5.10 queue-5.14 queue-5.15
> > 
> > That commit is in the current -rc releases right now.
> 
> Bah, there's stuff in-flight.
> 
> > The problem with this commit is that the cc_platform_has() function is
> > not present.  I thought about backporting it as well, but that seemed
> > odd as I do not think that feature is in the 5.15 and older kernels,
> > right?
> 
> The cc_platform_has() was a small set:
> 
> https://lore.kernel.org/r/YX%2B5ekjTbK3rhX%2BY@zn.tnic
> 
> which wants to keep all those checks confidential guests are going to do
> around the code, sane. So you don't really need it but...
> 
> > Or is it ok to take the cc_platform_has() function?
> 
> ... it will simplify all those backports which use it in the future. And
> we will use cc_platform_has() from now on in common code.
> 
> In any case, we're going to backport it into SLE just for that reason -
> so that it can ease backports and there's no kABI nightmares.

Ok, sounds good, I'll go queue them up now and see how the builds go to
save you the trouble of backporting into SLE...

greg k-h