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From: Song Liu <song@kernel.org>
Date: Fri, 12 Jan 2024 09:08:04 -0800
Message-ID: <CAPhsuW6KVN1c=dB1RXVQjygBevVcb_1qQJoLz3zA-qTVVmbCAw@mail.gmail.com>
Subject: Re: [PATCH 1/3] md: Remove deprecated CONFIG_MD_LINEAR
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-block@vger.kernel.org, Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>, 
	Neil Brown <neilb@suse.de>, Guoqing Jiang <guoqing.jiang@linux.dev>, 
	Mateusz Grzonka <mateusz.grzonka@intel.com>, Jes Sorensen <jes@trained-monkey.org>
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Hi Geert,

On Fri, Jan 12, 2024 at 1:28=E2=80=AFAM Geert Uytterhoeven <geert@linux-m68=
k.org> wrote:
>
[...]
>
> > --- a/drivers/md/Kconfig
> > +++ b/drivers/md/Kconfig
> > @@ -61,19 +61,6 @@ config MD_BITMAP_FILE
> >           various kernel APIs and can only work with files on a file sy=
stem not
> >           actually sitting on the MD device.
> >
> > -config MD_LINEAR
> > -       tristate "Linear (append) mode (deprecated)"
> > -       depends on BLK_DEV_MD
> > -       help
> > -         If you say Y here, then your multiple devices driver will be =
able to
> > -         use the so-called linear mode, i.e. it will combine the hard =
disk
> > -         partitions by simply appending one to the other.
> > -
> > -         To compile this as a module, choose M here: the module
> > -         will be called linear.
> > -
> > -         If unsure, say Y.
> > -
>
> Is this what you need to recover data from disks salvaged from a
> commercial NAS configured in JBOD mode?
> If yes, and there is no better way to do that, you probably do not
> want to drop this support.  Actual NAS systems running Linux might
> use this as well.

Thanks for the heads-up. I honestly don't know about this use case.
Where can I find/get more information about it?

Thanks,
Song