From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cornelia Huck Subject: Re: [RFC PATCH 2/2] virtio/s390: fix race in ccw_io_helper() Date: Thu, 20 Sep 2018 12:15:23 +0200 Message-ID: <20180920121523.4177db92.cohuck@redhat.com> References: <20180912140202.12292-1-pasic@linux.ibm.com> <20180912140202.12292-3-pasic@linux.ibm.com> <20180918204547.2500c848.cohuck@redhat.com> <20180919160759.731cb561.cohuck@redhat.com> <592b9fd1-0ab0-aa9f-31d7-a717610bd95c@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <592b9fd1-0ab0-aa9f-31d7-a717610bd95c@linux.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Halil Pasic Cc: linux-s390@vger.kernel.org, Colin Ian King , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org On Wed, 19 Sep 2018 18:56:45 +0200 Halil Pasic wrote: > On 09/19/2018 04:07 PM, Cornelia Huck wrote: > > Do you spot any other places where we may need to care about concurrent > > processing (like for the ->config area in the previous patch)? > > > > It is hard to tell, because: > * Synchronization external to the transport could make things work > out just fine. > * virtio_config_ops does not document these requirements if any. > * So it's up to the devices to use the stuff without shooting > themselves in the foot. > * virtio-pci does not seem to do more to avoid such problems that > we do. > > Back then when learning vritio-ccw I did ask myself such questions > and based on vrito-pci and I was like looks similar, should be > good enough. Yep, I agree. If there's nothing obvious, I think we should just leave it as it is now.