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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Fri, 6 Sep 2019 13:52:41 +0200
Message-ID: <CAJfpegudNVZitQ5L8gPvA45mRPFDk9fhyboceVW6xShpJ4mLww@mail.gmail.com>
Subject: Re: [PATCH 00/18] virtiofs: Fix various races and cleanups round 1
To:     Stefan Hajnoczi <stefanha@redhat.com>
Cc:     Vivek Goyal <vgoyal@redhat.com>, linux-fsdevel@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, virtio-fs@redhat.com,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        "Michael S. Tsirkin" <mst@redhat.com>
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On Fri, Sep 6, 2019 at 12:36 PM Stefan Hajnoczi <stefanha@redhat.com> wrote:
>
> On Fri, Sep 06, 2019 at 10:15:14AM +0200, Miklos Szeredi wrote:
> > On Thu, Sep 5, 2019 at 9:49 PM Vivek Goyal <vgoyal@redhat.com> wrote:
> > >
> > > Hi,
> > >
> > > Michael Tsirkin pointed out issues w.r.t various locking related TODO
> > > items and races w.r.t device removal.
> > >
> > > In this first round of cleanups, I have taken care of most pressing
> > > issues.
> > >
> > > These patches apply on top of following.
> > >
> > > git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git#virtiofs-v4
> > >
> > > I have tested these patches with mount/umount and device removal using
> > > qemu monitor. For example.
> >
> > Is device removal mandatory?  Can't this be made a non-removable
> > device?  Is there a good reason why removing the virtio-fs device
> > makes sense?
>
> Hot plugging and unplugging virtio PCI adapters is common.  I'd very
> much like removal to work from the beginning.

Can you give an example use case?

Thanks,
Miklos