netdev - Re: [Patch v4 04/13] x86/mm: Handle decryption/re-encryption of bss

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Date:   Mon, 9 Jan 2023 20:10:54 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     "Michael Kelley (LINUX)" <mikelley@...rosoft.com>
Cc:     "hpa@...or.com" <hpa@...or.com>, KY Srinivasan <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
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Subject: Re: [Patch v4 04/13] x86/mm: Handle decryption/re-encryption of
 bss_decrypted consistently

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?

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette