From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51520) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aj9VH-0006l7-1P for qemu-devel@nongnu.org; Thu, 24 Mar 2016 13:57:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aj9VC-0003Nj-2c for qemu-devel@nongnu.org; Thu, 24 Mar 2016 13:57:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48033) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aj9VB-0003NX-U1 for qemu-devel@nongnu.org; Thu, 24 Mar 2016 13:56:58 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 6432064449 for ; Thu, 24 Mar 2016 17:56:56 +0000 (UTC) From: Stefan Hajnoczi Date: Thu, 24 Mar 2016 17:56:47 +0000 Message-Id: <1458842214-11450-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [RFC 0/7] virtio: avoid exit() when device enters invalid states List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Fam Zheng , Stefan Hajnoczi , "Michael S. Tsirkin" The virtio code calls exit() when the device enters an invalid state. This means invalid vring indices and descriptor chains kill the VM. See the patch descriptions for why this is a bad thing. When the virtio device is in the broken state calls to virtqueue_pop() and friends will pretend the virtqueue is empty. This means the device will become isolated from guest activity until it is reset again. RFC because two things are missing: 1. Live migration support (subsection for broken flag?) 2. Auditing devices and replacing exit() calls there too Stefan Hajnoczi (7): virtio: fix stray tab character virtio: stop virtqueue processing if device is broken virtio: handle virtqueue_map_desc() errors virtio: handle virtqueue_get_avail_bytes() errors virtio: handle virtqueue_read_next_desc() errors virtio: handle virtqueue_num_heads() errors virtio: handle virtqueue_get_head() errors hw/virtio/virtio.c | 199 ++++++++++++++++++++++++++++++++++----------- include/hw/virtio/virtio.h | 3 + 2 files changed, 155 insertions(+), 47 deletions(-) -- 2.5.5