From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38448) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZNTtP-0007Oa-Hs for qemu-devel@nongnu.org; Thu, 06 Aug 2015 18:44:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZNTtM-0003Cy-C2 for qemu-devel@nongnu.org; Thu, 06 Aug 2015 18:44:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51339) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZNTtM-0003Ch-70 for qemu-devel@nongnu.org; Thu, 06 Aug 2015 18:44:04 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id 2624F3A9278 for ; Thu, 6 Aug 2015 22:35:55 +0000 (UTC) Date: Fri, 7 Aug 2015 01:31:21 +0300 From: "Michael S. Tsirkin" Message-ID: <20150807012346-mutt-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] virtio 1 issues List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Jason Wang Going over the code, I found a couple of issues. Recording them here since I won't be able to work on them until after the forum. 1. I realized we don't save/restore serialize the following fields in virtio pci: uint32_t dfselect; uint32_t gfselect; uint32_t guest_features[2]; struct { uint16_t num; bool enabled; uint32_t desc[2]; uint32_t avail[2]; uint32_t used[2]; } vqs[VIRTIO_QUEUE_MAX]; This isn't an issue unless VM is migrated during driver initialization. 2. ring resizing is broken - it actually has a comment: /* TODO: need a way to put num back on reset. */ guest that runs out of memory might down-size the ring. Afterwards, ring size won't come back up after reset - not nice. Given that the modern layout is disabled by default, I don't think these are release blockers. -- MST