From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37327) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dLrzA-0004s2-9K for qemu-devel@nongnu.org; Fri, 16 Jun 2017 10:12:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dLrz5-0006ih-6R for qemu-devel@nongnu.org; Fri, 16 Jun 2017 10:12:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54548) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dLrz5-0006hm-0V for qemu-devel@nongnu.org; Fri, 16 Jun 2017 10:12:23 -0400 Date: Fri, 16 Jun 2017 17:12:18 +0300 From: "Michael S. Tsirkin" Message-ID: <20170616171149-mutt-send-email-mst@kernel.org> References: <20170615163813.7255-1-stefanha@redhat.com> <20170615163813.7255-2-stefanha@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170615163813.7255-2-stefanha@redhat.com> Subject: Re: [Qemu-devel] [PATCH 1/5] virtio-pci: use ioeventfd even when KVM is disabled List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: qemu-devel@nongnu.org, Kevin Wolf , Pavel Butsykin On Thu, Jun 15, 2017 at 05:38:09PM +0100, Stefan Hajnoczi wrote: > Old kvm.ko versions only supported a tiny number of ioeventfds so > virtio-pci avoids ioeventfds when kvm_has_many_ioeventfds() returns 0. > > Do not check kvm_has_many_ioeventfds() when KVM is disabled since it > always returns 0. Since commit 8c56c1a592b5092d91da8d8943c17777d6462a6f > ("memory: emulate ioeventfd") it has been possible to use ioeventfds in > qtest or TCG mode. > > This patch makes -device virtio-blk-pci,iothread=iothread0 work even > when KVM is disabled. > > I have tested that virtio-blk-pci works under TCG both with and without > iothread. > > Cc: Michael S. Tsirkin > Signed-off-by: Stefan Hajnoczi Reviewed-by: Michael S. Tsirkin Do you want to merge this with the rest of the patchset, or should I? > --- > hw/virtio/virtio-pci.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index f9b7244..9f55476 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -1740,7 +1740,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) > bool pcie_port = pci_bus_is_express(pci_dev->bus) && > !pci_bus_is_root(pci_dev->bus); > > - if (!kvm_has_many_ioeventfds()) { > + if (kvm_enabled() && !kvm_has_many_ioeventfds()) { > proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD; > } > > -- > 2.9.4