From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: [BUG] race condition in blkfront (probably other frontends too). Date: Thu, 24 Jul 2008 16:15:07 +0200 Message-ID: <48888E6B.9090607@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Xen Development Mailing List List-Id: xen-devel@lists.xenproject.org Hi folks, I've just seen it with the block frontend, but most likely the other frontend drivers are affected too. The blkfront drivers goes into initialized state (in blkfront_probe), and *after* that xenbus_dev_probe sets a watch on the state node of the device. That leaves a race window open for the backend going into connected state before the watch is active. If that happens the frontend doesn't notice the backend is ready and never ever goes into connected state ... cheers, Gerd -- http://kraxel.fedorapeople.org/xenner/