** Changed in: qemu (Ubuntu Vivid) Status: In Progress => Invalid
** Changed in: qemu (Ubuntu Vivid) Assignee: Liang Chen (cbjchen) => (unassigned) ** No longer affects: qemu (Ubuntu Vivid) -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1546445 Title: support vhost user without specifying vhostforce Status in Ubuntu Cloud Archive: In Progress Status in Ubuntu Cloud Archive kilo series: In Progress Status in QEMU: Fix Released Status in qemu package in Ubuntu: Fix Released Status in qemu source package in Wily: Fix Released Bug description: [Impact] * vhost-user falls back to virtio-net which causes performance lose without specifying the vhostforce option. But it should be the default behavior for vhost-user, since guests using PMD doesn't support msi-x. [Test Case] create a vhost-user virtio backend without specifying the vhostforce option, i.e. -netdev type=vhost-user,id=mynet1,chardev=<char_dev_for_the_controll_channel> start the VM vhost-user is not enabled [Regression Potential] * none vhost user nic doesn't support non msi guests(like pxe stage) by default. Vhost user nic can't fall back to qemu like normal vhost net nic does. So we should enable it for non msi guests. The problem has been fix in qemu upstream - http://git.qemu.org/?p=qemu.git;a=commitdiff;h=24f938a682d934b133863eb421aac33592f7a09e. And the patch needs to be backported to 1:2.2+dfsg-5expubuntu9.8 . To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-archive/+bug/1546445/+subscriptions