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From: Ard Biesheuvel <ardb@kernel.org>
Date: Wed, 31 Jan 2024 10:59:34 +0100
Message-ID: <CAMj1kXFrF4F0UdBoPLMkRS26CRKmDw6_+-zeRgNEmdOn11fsug@mail.gmail.com>
Subject: Re: [PATCH v3 02/19] x86/boot: Move mem_encrypt= parsing to the decompressor
To: Borislav Petkov <bp@alien8.de>
Cc: Ard Biesheuvel <ardb+git@google.com>, linux-kernel@vger.kernel.org, 
	Kevin Loughlin <kevinloughlin@google.com>, Tom Lendacky <thomas.lendacky@amd.com>, 
	Dionna Glaze <dionnaglaze@google.com>, Thomas Gleixner <tglx@linutronix.de>, 
	Ingo Molnar <mingo@redhat.com>, Dave Hansen <dave.hansen@linux.intel.com>, 
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>, Nathan Chancellor <nathan@kernel.org>, 
	Nick Desaulniers <ndesaulniers@google.com>, Justin Stitt <justinstitt@google.com>, 
	Kees Cook <keescook@chromium.org>, Brian Gerst <brgerst@gmail.com>, linux-arch@vger.kernel.org, 
	llvm@lists.linux.dev
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On Wed, 31 Jan 2024 at 10:30, Borislav Petkov <bp@alien8.de> wrote:
>
> On Wed, Jan 31, 2024 at 10:12:13AM +0100, Ard Biesheuvel wrote:
> > The reason we need two flags is because there is no default value to
> > use when the command line param is absent.
>
> I think absent means memory encryption disabled like with every other
> option which is not present...
>
> > There is CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT but that one is AMD
>
> ... yes, and I'm thinking that it is time we kill this. I don't think
> anything uses it. It was meant well at the time.
>
> Let's wait for Tom to wake up first, though, as he might have some
> objections...
>

OK, yeah, that would help.

AIUI this is for SME only anyway - SEV ignores this, and I suppose TDX
will do the same.