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Date:   Tue, 30 May 2023 14:39:15 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Loic Poulain <loic.poulain@linaro.org>
Cc:     corbet@lwn.net, viro@zeniv.linux.org.uk,
        linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] init: Add support for rootwait timeout parameter
Message-ID: <20230530-anziehen-brokkoli-4c1365e888ea@brauner>
References: <20230526130716.2932507-1-loic.poulain@linaro.org>
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 <CAMZdPi_WE7eegcn3V+7tUsJL2GoGottz2fGY14tkmqG9Tgdbhg@mail.gmail.com>
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On Tue, May 30, 2023 at 01:23:50PM +0200, Loic Poulain wrote:
> Hi Christian,
> 
> On Tue, 30 May 2023 at 11:45, Christian Brauner <brauner@kernel.org> wrote:
> >
> > On Fri, May 26, 2023 at 03:07:16PM +0200, Loic Poulain wrote:
> > > Add an optional timeout arg to 'rootwait' as the maximum time in
> > > seconds to wait for the root device to show up before attempting
> > > forced mount of the root filesystem.
> > >
> > > This can be helpful to force boot failure and restart in case the
> > > root device does not show up in time, allowing the bootloader to
> > > take any appropriate measures (e.g. recovery, A/B switch, retry...).
> > >
> > > In success case, mounting happens as soon as the root device is ready,
> > > contrary to the existing 'rootdelay' parameter (unconditional delay).
> > >
> > > Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> > > ---
> >
> > Not terribly opposed and not terribly convinced yet.
> > So, we have rootdelay= with a timeout parameter that allows to specify a
> > delay before attempting to mount the root device. And we have rootwait
> > currently as an indefinite wait. Adding a timeout for rootwait doesn't
> > seem crazy and is backwards compatible. But there's no mention of any
> > concrete users or use-case for this which is usually preferable. If this
> > is just "could be useful for someone eventually" it's way less desirable
> > to merge this than when it's "here's a/multiple user/users"... So I
> > would love to see a use-case described here.
> 
> I can integrate the following use case into a v2 if you think it makes sense:

Yes, please.