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From:   Roman Stratiienko <roman.stratiienko@globallogic.com>
Date:   Thu, 13 Jun 2019 19:21:43 +0300
Message-ID: <CAODwZ7so4cVVJmPHXGGOxKRO_0L2NjZJac73wfaHPV7ZN6ce1g@mail.gmail.com>
Subject: Re: [PATCH 2/2] nbd: add support for nbd as root device
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     linux-kernel@vger.kernel.org, nbd@other.debian.org,
        Aleksandr Bulyshchenko <A.Bulyshchenko@globallogic.com>,
        linux-block@vger.kernel.org, axboe@kernel.dkn.org
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> I don't doubt you have a good reason to want it, I'm just not clear on why an
> initramfs isn't an option?  You have this special kernel with your special
> option, and you manage to get these things to boot your special kernel right?
> So why is a initramfs with a tiny nbd-client binary in there not an option?
>
> Also I mean that there are a bunch of different nbd servers out there.  We have
> our own here at Facebook, qemu has one, IIRC there's a ceph one.  They all have
> their own connection protocols.  The beauty of NBD is that it doesn't have to
> know about that part, it just does the block device part, and I'd really rather
> leave it that way.  Thanks,
>
> Josef


The only reason I prefer embed client into the kernel is to save
valuable engineering time creating and supporting custom initramfs,
that is not so easy especially on Android-based systems.

Taking into account that if using NBD and creating custom initramfs
required only for automated testing, many companies would choose
manual deployment instead, that is bad for the human progress.

I believe that all users of non-standard NBD handshake protocols could
continue to use custom nbd-clients.

Either you accept this patch or not I would like to pass review from
maintainers and other persons that was involved in NBD development,
thus making a step closer to get this mainlined in some future.

--
Regards,
Roman