From patchwork Fri Feb 27 18:19:06 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 444476 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id CD2751400F1 for ; Sat, 28 Feb 2015 06:02:16 +1100 (AEDT) Received: from localhost ([::1]:38482 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YRQAw-0005wV-MJ for incoming@patchwork.ozlabs.org; Fri, 27 Feb 2015 14:02:14 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41826) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YRPXp-0001oy-Mm for qemu-devel@nongnu.org; Fri, 27 Feb 2015 13:21:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YRPXj-0002Or-9e for qemu-devel@nongnu.org; Fri, 27 Feb 2015 13:21:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42917) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YRPXj-0002Oe-1Q for qemu-devel@nongnu.org; Fri, 27 Feb 2015 13:21:43 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t1RILbRg009245 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 27 Feb 2015 13:21:37 -0500 Received: from localhost (ovpn-112-20.ams2.redhat.com [10.36.112.20]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t1RILZqe006592; Fri, 27 Feb 2015 13:21:36 -0500 From: Stefan Hajnoczi To: Date: Fri, 27 Feb 2015 18:19:06 +0000 Message-Id: <1425061147-1411-69-git-send-email-stefanha@redhat.com> In-Reply-To: <1425061147-1411-1-git-send-email-stefanha@redhat.com> References: <1425061147-1411-1-git-send-email-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-MIME-Autoconverted: from 8bit to quoted-printable by mx1.redhat.com id t1RILbRg009245 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: =?UTF-8?q?Marc=20Mar=C3=AD?= , Peter Maydell , Stefan Hajnoczi Subject: [Qemu-devel] [PULL 68/69] libqos: Solve bug in interrupt checking when using MSIX in virtio-pci.c X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Marc Marí The MSIX interrupt was always acked without checking its value, which caused a race condition. If the ISR was raised between the read and the acking, the ISR was never detected and it timed out. Signed-off-by: Marc Marí Reviewed-by: John Snow Tested-by: John Snow Message-id: 1424795655-16952-1-git-send-email-marc.mari.barcelo@gmail.com Signed-off-by: Stefan Hajnoczi --- tests/libqos/virtio-pci.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/tests/libqos/virtio-pci.c b/tests/libqos/virtio-pci.c index 046a316..f9fb924 100644 --- a/tests/libqos/virtio-pci.c +++ b/tests/libqos/virtio-pci.c @@ -142,8 +142,12 @@ static bool qvirtio_pci_get_queue_isr_status(QVirtioDevice *d, QVirtQueue *vq) return qpci_msix_pending(dev->pdev, vqpci->msix_entry); } else { data = readl(vqpci->msix_addr); - writel(vqpci->msix_addr, 0); - return data == vqpci->msix_data; + if (data == vqpci->msix_data) { + writel(vqpci->msix_addr, 0); + return true; + } else { + return false; + } } } else { return qpci_io_readb(dev->pdev, dev->addr + QVIRTIO_PCI_ISR_STATUS) & 1; @@ -162,8 +166,12 @@ static bool qvirtio_pci_get_config_isr_status(QVirtioDevice *d) return qpci_msix_pending(dev->pdev, dev->config_msix_entry); } else { data = readl(dev->config_msix_addr); - writel(dev->config_msix_addr, 0); - return data == dev->config_msix_data; + if (data == dev->config_msix_data) { + writel(dev->config_msix_addr, 0); + return true; + } else { + return false; + } } } else { return qpci_io_readb(dev->pdev, dev->addr + QVIRTIO_PCI_ISR_STATUS) & 2;