Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 28 Jun 2022 02:44:40 -0400
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jason Wang <jasowang@redhat.com>
Cc:     Cornelia Huck <cohuck@redhat.com>,
        Halil Pasic <pasic@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        linux-s390@vger.kernel.org,
        virtualization <virtualization@lists.linux-foundation.org>,
        kvm <kvm@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ben Hutchings <ben@decadent.org.uk>,
        David Hildenbrand <david@redhat.com>
Subject: Re: [PATCH V3] virtio: disable notification hardening by default
Message-ID: <20220628023832-mutt-send-email-mst@kernel.org>
References: <20220624022622-mutt-send-email-mst@kernel.org>
 <CACGkMEuurobpUWmDL8zmZ6T6Ygc0OEMx6vx2EDCSoGNnZQ0r-w@mail.gmail.com>
 <20220627024049-mutt-send-email-mst@kernel.org>
 <CACGkMEvrDXDN7FH1vKoYCob2rkxUsctE_=g61kzHSZ8tNNr6vA@mail.gmail.com>
 <20220627053820-mutt-send-email-mst@kernel.org>
 <CACGkMEvcs+9_SHmO1s3nyzgU7oq7jhU2gircVVR3KDsGDikh5Q@mail.gmail.com>
 <20220628004614-mutt-send-email-mst@kernel.org>
 <CACGkMEsC4A+3WejLSOZoH3enXtai=+JyRNbxcpzK4vODYzhaFw@mail.gmail.com>
 <20220628022035-mutt-send-email-mst@kernel.org>
 <CACGkMEt=go5qAH+P0to6yyE2dPhyfFmOQP0jfuj=57PmD7Y3zg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CACGkMEt=go5qAH+P0to6yyE2dPhyfFmOQP0jfuj=57PmD7Y3zg@mail.gmail.com>
Precedence: bulk

On Tue, Jun 28, 2022 at 02:32:19PM +0800, Jason Wang wrote:
> > Question is are there drivers which kick before they are ready
> > to handle callbacks?
> 
> Let me try to have a look at all the drivers to answer this.

One thing to note is that I consider hardening probe and
hardening remove separate features. I think that at this point
for secured guests it is prudent to outright block device
removal - we have been finding races in removal for years.
Note sure there's a flag for that but it's probably not too hard to add
e.g. to pci core.

-- 
MST