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Date:   Thu, 15 Apr 2021 16:54:11 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        Enrico Granata <egranata@google.com>, jasowang@redhat.com,
        pbonzini@redhat.com, axboe@kernel.dk,
        virtualization@lists.linux-foundation.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] virtio_blk: Add support for lifetime feature
Message-ID: <20210415155411.GA2090820@infradead.org>
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On Mon, Apr 12, 2021 at 08:00:24AM -0400, Michael S. Tsirkin wrote:
> On Mon, Apr 12, 2021 at 10:42:17AM +0100, Christoph Hellwig wrote:
> > A note to the virtio committee:  eMMC is the worst of all the currently
> > active storage standards by a large margin.  It defines very strange
> > ad-hoc interfaces that expose very specific internals and often provides
> > very poor abstractions.
> 
> Are we talking about the lifetime feature here?  UFS has it too right?

Ok, the wide margin above ignores UFS, which has a lot of the same
issues as EMMC, just a little less cruft.

> It's not too late to
> change things if necessary... it would be great if you could provide
> more of the feedback on this on the TC mailing list.

I think the big main issue here is that it just forwards an awkwardly
specific concept through virtio.  If we want a virtio feature it really
needs to stand a lone and be properly documented without referring to
external specifications that are not openly available.

> > It would be great it you could reach out to the
> > wider storage community before taking bad ideas from the eMMC standard
> > and putting it into virtio.
> 
> Noted.  It would be great if we had more representation from the storage
> community ... meanwhile what would a good forum for this be?
> linux-block@vger.kernel.org ?

At least for linux, yes.