Date:   Thu, 9 Dec 2021 11:03:07 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Hugh Dickins <hughd@google.com>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Anjaneya Chagam <anjaneya.chagam@intel.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Mike Rapoport <rppt@kernel.org>
Subject: Re: 5.16-rc: "x86/boot: Pull up cmdline" breaks mem=
Message-ID: <YbHUW1KTfvJtxNwP@zn.tnic>
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Hi Hugh,

On Wed, Dec 08, 2021 at 09:44:54PM -0800, Hugh Dickins wrote:
> Bad news, I'm afraid: I boot with "mem=1G" on the cmdline for testing,
> which worked fine on 5.16-rc1, but does not work on 5.16-rc2 onwards.
>
> Bisection arrived at 8d48bf8206f7 ("x86/boot: Pull up cmdline preparation
> and early param parsing"); and reverting c0f2077baa41 ("x86/boot: Mark
> prepare_command_line() __init") then 8d48bf820cf7 does fix my "mem=1G".

Yeah, I had a bug reporter report breaking on his machine but he didn't
respond to my request for additional details.

Can you pls send me full dmesg and .config of the -rc1 kernel which
still boots fine. I'd like to try to repro.

> I have not tried 5.15-stable, but guess that is likewise afflicted.

Right.

> Sympathy, but no suggestions from me: early init ordering is hard!

Tell me about it! This is the 4 or so "fix" which tries to address
fallout from Mike and mine's attempt to sort out memblock ordering
during early boot.

Thx.

-- 
Regards/Gruss,
    Boris.

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