RE: [Patch v4 04/13] x86/mm: Handle decryption/re-encryption of bss_decrypted consistently

Michael Kelley (LINUX)
2023-01-09T19:15:13Z

From: Borislav Petkov <bp@alien8.de> Sent: Monday, January 9, 2023 11:11 AM
>
> On Thu, Dec 29, 2022 at 04:25:16PM +0000, Michael Kelley (LINUX) wrote:
> > I'm ambivalent on the backport to stable. One might argue that older
> > kernel versions are conceptually wrong in using different conditions for
> > the decryption and re-encryption. But as you said, they aren't broken
> > from a practical standpoint because sme_me_mask and
> > CC_ATTR_MEM_ENCRYPT are equivalent prior to my patch set. However,
> > the email thread with Sathyanarayanan Kuppuswamy, Tom Lendacky,
> > and Dexuan Cui concluded that a Fixes: tag is appropriate.
>
> Right, just talked to Tom offlist.
>
> A Fixes tag triggers a lot of backporting activity and if it is not really
> needed, then let's leave it out.
>
> If distros decide to pick up vTOM support, then they'll pick up the whole set
> anyway.
>
> And if we decide we really need it backported for whatever reason, we will
> simply send it into stable and the same backporting activity will be triggered
> then. But then we'd at least have a concrete reason for it.
>
> Makes sense?
>

Yep, that matches my thinking. I've avoided marking something for stable unless
it fixes something that is actually broken.

Michael