From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49791) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewty5-0002bc-M8 for qemu-devel@nongnu.org; Fri, 16 Mar 2018 14:20:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ewty2-0000JC-4p for qemu-devel@nongnu.org; Fri, 16 Mar 2018 14:20:41 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:45382 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ewty1-0000Io-VR for qemu-devel@nongnu.org; Fri, 16 Mar 2018 14:20:38 -0400 Date: Fri, 16 Mar 2018 20:20:21 +0200 From: "Michael S. Tsirkin" Message-ID: <1521224390-425343-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Qemu-devel] [PATCH] vhost-user: avoid misaligned access List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Jay Zhou We can't pass a pointer to memory field directly since it's within a packed structure, so isn't aligned. Pass a pointer on stack and copy. Fixes: 30c4cc7 ("vhost: used_memslots refactoring") Cc: Jay Zhou Signed-off-by: Michael S. Tsirkin --- I had to apply this to fix make check errors with clang. Pls review, test and ack. Thanks! hw/virtio/vhost-user.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index c12fdd9..a44ee7f 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -396,6 +396,7 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, bool reply_supported = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_REPLY_ACK); VhostUserMsg msg_reply; + VhostUserMemory memory = {}; int region_i, msg_i; VhostUserMsg msg = { @@ -407,10 +408,11 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev, msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; } - if (vhost_user_prepare_msg(dev, &msg.payload.memory, fds) < 0) { + if (vhost_user_prepare_msg(dev, &memory, fds) < 0) { error_report("Failed preparing vhost-user memory table msg"); return -1; } + msg.payload.memory = memory; fd_num = msg.payload.memory.nregions; @@ -549,16 +551,19 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, .hdr.request = VHOST_USER_SET_MEM_TABLE, .hdr.flags = VHOST_USER_VERSION, }; + VhostUserMemory memory = {}; if (reply_supported) { msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; } - if (vhost_user_prepare_msg(dev, &msg.payload.memory, fds) < 0) { + if (vhost_user_prepare_msg(dev, &memory, fds) < 0) { error_report("Failed preparing vhost-user memory table msg"); return -1; } + msg.payload.memory = memory; + fd_num = msg.payload.memory.nregions; if (!fd_num) { @@ -1575,8 +1580,11 @@ static void vhost_user_set_used_memslots(struct vhost_dev *dev) { int fds[VHOST_MEMORY_MAX_NREGIONS]; VhostUserMsg msg; + VhostUserMemory memory = {}; + + vhost_user_prepare_msg(dev, &memory, fds); - vhost_user_prepare_msg(dev, &msg.payload.memory, fds); + msg.payload.memory = memory; } const VhostOps user_ops = { -- MST