From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60993) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cW3Mz-0002zU-Tw for qemu-devel@nongnu.org; Tue, 24 Jan 2017 10:50:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cW3Mz-0000XQ-5Q for qemu-devel@nongnu.org; Tue, 24 Jan 2017 10:50:53 -0500 References: <1485132904-17632-1-git-send-email-zhaoshenglong@huawei.com> <20170123180247-mutt-send-email-mst@kernel.org> <49fcc1e0-f439-9212-25f1-9b8dce6462cc@redhat.com> <20170123190257-mutt-send-email-mst@kernel.org> <5760ee8c-f567-0dfd-456f-65f8957b22e2@redhat.com> <20170124164204-mutt-send-email-mst@kernel.org> <9a61e616-9bf8-b4ff-43b9-68f1c908b910@redhat.com> <20170124170514-mutt-send-email-mst@kernel.org> From: Paolo Bonzini Message-ID: Date: Tue, 24 Jan 2017 16:50:44 +0100 MIME-Version: 1.0 In-Reply-To: <20170124170514-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V2] virtio: Fix no interrupt when not creating msi controller List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: Shannon Zhao , qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, christoffer.dall@linaro.org On 24/01/2017 16:05, Michael S. Tsirkin wrote: >> >> So we have four cases: >> >> - assign with emulated irqfd + ISR >> - assign with emulated irqfd >> - assign with irqfd >> - deassign >> >> Currently we don't distinguish the first two, so (which I don't like) >> Shannon's patch ends up setting ISR twice. > > I don't see this yet - where is it set twice? Once in virtio_notify_irqfd, once in virtio_queue_guest_notifier_read. Unfortunately, for virtio-blk + MSI + KVM + old Windows drivers we need the one in virtio_notify_irqfd. For virtio-net + vhost + INTx we need the one in virtio_queue_guest_notifier_read.