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From:   "Eric W. Biederman" <ebiederm@xmission.com>
To:     Mike Christie <michael.christie@oracle.com>
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Date:   Wed, 14 Jun 2023 01:02:58 -0500
In-Reply-To: <cfbf1a0d-5d62-366f-f32f-6c63b151489e@oracle.com> (Mike
        Christie's message of "Tue, 6 Jun 2023 15:38:04 -0500")
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Subject: Can vhost translate to io_uring?
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I am sad my idea for simplifying things did not work out.


Let's try an even bigger idea to reduce maintenance and simplify things.

Could vhost depend on io_uring?

Could vhost just be a translation layer of existing vhost requests to
io_uring requests?

At a quick glance it looks like io_uring already supports the
functionality that vhost supports (which I think is networking and
scsi).

If vhost could become a translation layer that would allow removing
the vhost worker and PF_USER_WORKER could be removed completely,
leaving only PF_IO_WORKER.


I suggest this because a significant vhost change is needed because in
the long term the hacks in exec and coredump are not a good idea.  Which
means something like my failed "[PATCH v3] fork, vhost: Use CLONE_THREAD
to fix freezer/ps regression".

If we have to go to all of the trouble of reworking things it why can't
we just make io_uring do all of the work?

Eric