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From:   Song Liu <songliubraving@fb.com>
To:     Jason Baron <jbaron@akamai.com>
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Subject: Re: [PATCH v2] md/raid0: add config parameters to specify zone layout
Thread-Topic: [PATCH v2] md/raid0: add config parameters to specify zone
 layout
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Date:   Fri, 24 Apr 2020 23:22:23 +0000
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> On Mar 30, 2020, at 9:00 AM, Jason Baron <jbaron@akamai.com> wrote:
>=20
> Let's add some CONFIG_* options to directly configure the raid0 layout
> if you know in advance how your raid0 array was created. This can be
> simpler than having to manage module or kernel command-line parameters.
>=20
> If the raid0 array was created by a pre-3.14 kernel, use
> RAID0_ORIG_LAYOUT. If the raid0 array was created by a 3.14 or newer
> kernel then select RAID0_ALT_MULTIZONE_LAYOUT. Otherwise, the default
> setting is RAID0_LAYOUT_NONE, in which case the current behavior of
> needing to specify a module parameter raid0.default_layout=3D1|2 is
> preserved.
>=20
> Cc: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
> Cc: NeilBrown <neilb@suse.de>
> Cc: Song Liu <songliubraving@fb.com>
> Signed-off-by: Jason Baron <jbaron@akamai.com>

This patch looks good. However, I am not sure whether the user will=20
recompile the kernel for a different default value. Do you have real
world use case for this?

Thanks,
Song