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Date:   Tue, 27 Oct 2020 17:31:02 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Arvind Sankar <nivedita@alum.mit.edu>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Kees Cook <keescook@chromium.org>,
        Joerg Roedel <jroedel@suse.de>
Subject: Re: RFC x86/boot/64: BOOT_PGT_SIZE definition for compressed kernel
Message-ID: <20201027143102.ugco5dmixu66fjsc@box>
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 <20201027124007.xkkseswwgerlzlsl@box>
 <20201027131617.GA1743199@rani.riverdale.lan>
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On Tue, Oct 27, 2020 at 09:16:17AM -0400, Arvind Sankar wrote:
> The #PF handler is already there now with the SEV-ES series, but I agree
> it would still complicate things. It's simpler to just increase
> BOOT_PGT_SIZE and make it unconditional (i.e. bump it to say 32 or 64
> even if !KASLR). It's @nobits anyway so it would not increase the size
> of the bzImage, just require a slightly larger memory allocation by the
> bootloader.

I guess it's fine. But I'm worried we leave the picture in the same
fragile state. We still rely on the magic number.

-- 
 Kirill A. Shutemov