From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:33105) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XRMB5-00012n-LK for qemu-devel@nongnu.org; Tue, 09 Sep 2014 10:13:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XRMAy-0007TK-Hk for qemu-devel@nongnu.org; Tue, 09 Sep 2014 10:13:51 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:37808) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XRMAy-0007Sy-C9 for qemu-devel@nongnu.org; Tue, 09 Sep 2014 10:13:44 -0400 Received: from /spool/local by e8.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 9 Sep 2014 10:13:43 -0400 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable From: Michael Roth In-Reply-To: <1410192283-4026-1-git-send-email-mst@redhat.com> References: <1410192283-4026-1-git-send-email-mst@redhat.com> Message-ID: <20140909141338.16792.15555@loki> Date: Tue, 09 Sep 2014 09:13:38 -0500 Subject: Re: [Qemu-devel] [PATCH] virtio-pci: enable bus master for old guests List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" , qemu-devel@nongnu.org Cc: Jan Kiszka , qemu-stable@nongnu.org, Anthony Liguori Quoting Michael S. Tsirkin (2014-09-08 11:05:02) > commit cc943c36faa192cd4b32af8fe5edb31894017d35 > pci: Use bus master address space for delivering MSI/MSI-X messages > breaks virtio-net for rhel6.[56] x86 guests because they don't > enable bus mastering for virtio PCI devices > = > Old guests forgot to enable bus mastering, enable it > automatically on DRIVER_OK. > = > Note: we should either back out the original patch from > stable or apply this one on top. I've already backed out the other patch, and it looks we'll have to stick with that for now with the release being tomorrow. Will queue these back up for 2.1.2 though. > = > Cc: qemu-stable@nongnu.org > Reported-by: Greg Kurz > Signed-off-by: Jan Kiszka > Signed-off-by: Michael S. Tsirkin > --- > hw/virtio/virtio-pci.c | 2 ++ > 1 file changed, 2 insertions(+) > = > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index ddb5da1..af937d2 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -320,6 +320,8 @@ static void virtio_ioport_write(void *opaque, uint32_= t addr, uint32_t val) > if ((val & VIRTIO_CONFIG_S_DRIVER_OK) && > !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { > proxy->flags |=3D VIRTIO_PCI_FLAG_BUS_MASTER_BUG; > + memory_region_set_enabled(&proxy->pci_dev.bus_master_enable_= region, > + true); > } > break; > case VIRTIO_MSI_CONFIG_VECTOR: > -- = > MST