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Date: Mon, 20 Feb 2017 19:46:58 +0100
From: Daniel Kiper <dkiper@net-space.pl>
To: The development of GNU GRUB <grub-devel@gnu.org>
Cc: Daniel Kiper <dkiper@net-space.pl>, Juergen Gross <jgross@suse.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Matt Fleming <matt@codeblueprint.co.uk>, phcoder@gmail.com,
        Daniel Kiper <daniel.kiper@oracle.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Alexander Graf <agraf@suse.de>,
        arvidjaar@gmail.com, "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Chao Peng <chao.p.peng@linux.intel.com>,
        Al Viro <viro@zeniv.linux.org.uk>, Andy Lutomirski <luto@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Borislav Petkov <bp@suse.de>,
        Amnon Ilan <ailan@redhat.com>, Thomas Garnier <thgarnie@google.com>,
        konrad.wilk@oracle.com
Subject: Re: [RFC PATCH] x86/boot: make ELF kernel multiboot-able
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On Thu, Feb 16, 2017 at 09:00:05PM -0800, H. Peter Anvin wrote:
> On 02/16/17 15:27, Daniel Kiper wrote:
> > That is obvious. Do you think that Multiboot/Multiboot2 protocols are
> > substantially suboptimal?
>
> Yes.  They push a lot of things into the bootloader for no good reason,

I have not seen anything in Multiboot(2) specs which stipulates that every
bootloader must implement all features. If somebody needs minimal Multiboot(2)
compatible bootloader he/she can do that. Just parse Multiboot(2) header and
provide, let's call it in that way, empty boot data. Is it difficult?

> thus tying the kernel's hands and making the whole boot process more
> fragile.

Every kernel may take from the bootloader via Multiboot(2) what it needs.
No more no less. There is no requirement to use all data provided by
the bootloader.

> It isn't either like Grub has been very good about keeping to any spec,
> their own or others.

Could you be more precise?

Daniel