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From:   Sedat Dilek <sedat.dilek@gmail.com>
Date:   Wed, 1 Apr 2020 12:00:35 +0200
Message-ID: <CA+icZUXufL22Fp7ge9uzZ7K5K2MfX-C+HJcDcr06KKNYQOBXoA@mail.gmail.com>
Subject: Re: [PATCH v3 0/8] Add support for ZSTD-compressed kernel and initramfs
To:     Adam Borowski <kilobyte@angband.pl>
Cc:     Nick Terrell <terrelln@fb.com>,
        Nick Terrell <nickrterrell@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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On Wed, Apr 1, 2020 at 9:27 AM Adam Borowski <kilobyte@angband.pl> wrote:
>
> On Wed, Apr 01, 2020 at 02:52:06AM +0000, Nick Terrell wrote:
> > > On Mar 31, 2020, at 8:11 AM, Sedat Dilek <sedat.dilek@gmail.com> wrot=
e:
> > > On Tue, Mar 31, 2020 at 6:15 AM Nick Terrell <terrelln@fb.com> wrote:

[...]

> > I don=E2=80=99t expect any distro specific changes are required to cont=
inue operating
> > as-is. However, if a distro wanted to switch to a zstd compressed initr=
amfs
> > they would need to update their toolchain to compress with zstd.
>
> Just setting COMPRESS=3Dzstd is enough -- it'll say:
> W: Unknown compression command zstd
> but will do everything right.
>
> Also, just minutes ago someone filed https://bugs.debian.org/955469
>

Hi Adam,

thanks for your feedback and the pointer to the Debian bug #955469.

With "distro-specific changes" I meant the ones to userland - for
Debian - namely initramfs-tools{,-core} packages.
For generating, inspecting and unpacking an initramfs the Debian way
you need a bit more.

In the Bug-BR a patch called "enable_zstd.patch" is attached - seems
to have all what I mentioned in [1].

Regards,
- Sedat -

[1] LINK: https://lore.kernel.org/lkml/CA+icZUXCn2an9aNDrm+-eneSAOyGibz0W1x=
YhwkA5k3B3U-5vQ@mail.gmail.com/