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Date:   Fri, 10 Jul 2020 11:33:09 -0400
From:   Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To:     Stefano Garzarella <sgarzare@redhat.com>
Cc:     Jens Axboe <axboe@kernel.dk>, Sargun Dhillon <sargun@sargun.me>,
        Kees Cook <keescook@chromium.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Jann Horn <jannh@google.com>, Aleksa Sarai <asarai@suse.de>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        io-uring@vger.kernel.org, Alexander Viro <viro@zeniv.linux.org.uk>,
        Jeff Moyer <jmoyer@redhat.com>
Subject: Re: [PATCH RFC 0/3] io_uring: add restrictions to support untrusted
 applications and guests
Message-ID: <20200710153309.GA4699@char.us.oracle.com>
References: <20200710141945.129329-1-sgarzare@redhat.com>
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.snip..
> Just to recap the proposal, the idea is to add some restrictions to the
> operations (sqe, register, fixed file) to safely allow untrusted applications
> or guests to use io_uring queues.

Hi!

This is neat and quite cool - but one thing that keeps nagging me is
what how much overhead does this cut from the existing setup when you use
virtio (with guests obviously)? That is from a high level view the
beaty of io_uring being passed in the guest is you don't have the
virtio ring -> io_uring processing, right?

Thanks!