From patchwork Fri Dec 8 07:45:12 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Ladi Prosek X-Patchwork-Id: 10101717 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4F15860325 for ; Fri, 8 Dec 2017 07:47:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4088928AFB for ; Fri, 8 Dec 2017 07:47:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3434828AFD; Fri, 8 Dec 2017 07:47:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A27D628AFB for ; Fri, 8 Dec 2017 07:47:11 +0000 (UTC) Received: from localhost ([::1]:35895 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eNDNG-0003LQ-Rc for patchwork-qemu-devel@patchwork.kernel.org; Fri, 08 Dec 2017 02:47:10 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58492) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eNDLg-00024x-5S for qemu-devel@nongnu.org; Fri, 08 Dec 2017 02:45:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eNDLe-0005jI-Ba for qemu-devel@nongnu.org; Fri, 08 Dec 2017 02:45:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58784) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eNDLe-0005gs-4Z for qemu-devel@nongnu.org; Fri, 08 Dec 2017 02:45:30 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 41DE94A6F3; Fri, 8 Dec 2017 07:45:29 +0000 (UTC) Received: from dhcp-1-107.brq.redhat.com (ovpn-204-198.brq.redhat.com [10.40.204.198]) by smtp.corp.redhat.com (Postfix) with ESMTP id A97EB1964B; Fri, 8 Dec 2017 07:45:27 +0000 (UTC) From: Ladi Prosek To: qemu-devel@nongnu.org Date: Fri, 8 Dec 2017 08:45:12 +0100 Message-Id: <20171208074515.1553-2-lprosek@redhat.com> In-Reply-To: <20171208074515.1553-1-lprosek@redhat.com> References: <20171208074515.1553-1-lprosek@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Fri, 08 Dec 2017 07:45:29 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 1/4] ivshmem: Don't update non-existent MSI routes X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: geoff@hostfission.com, pbonzini@redhat.com, armbru@redhat.com, marcandre.lureau@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP As of commit 660c97eef6f8 ("ivshmem: use kvm irqfd for msi notifications"), QEMU crashes with: kvm_irqchip_commit_routes: Assertion `ret == 0' failed. if the ivshmem device is configured with more vectors than what the server supports. This is caused by the ivshmem_vector_unmask() being called on vectors that have not been initialized by ivshmem_add_kvm_msi_virq(). This commit fixes it by adding a simple check to the mask and unmask callbacks. Note that the opposite mismatch, if the server supplies more vectors than what the device is configured for, is already handled and leads to output like: Too many eventfd received, device has 1 vectors To reproduce the assert, run: ivshmem-server -n 0 and QEMU with: -device ivshmem-doorbell,chardev=iv -chardev socket,path=/tmp/ivshmem_socket,id=iv then load the Windows driver, at the time of writing available at: https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem The issue is believed to have been masked by other guest drivers, notably Linux ones, not enabling MSI-X on the device. Fixes: 660c97eef6f8 ("ivshmem: use kvm irqfd for msi notifications") Signed-off-by: Ladi Prosek Reviewed-by: Marc-André Lureau Reviewed-by: Markus Armbruster --- hw/misc/ivshmem.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index a5a46827fe..6e46669744 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -317,6 +317,10 @@ static int ivshmem_vector_unmask(PCIDevice *dev, unsigned vector, int ret; IVSHMEM_DPRINTF("vector unmask %p %d\n", dev, vector); + if (!v->pdev) { + error_report("ivshmem: vector %d route does not exist", vector); + return -EINVAL; + } ret = kvm_irqchip_update_msi_route(kvm_state, v->virq, msg, dev); if (ret < 0) { @@ -331,12 +335,16 @@ static void ivshmem_vector_mask(PCIDevice *dev, unsigned vector) { IVShmemState *s = IVSHMEM_COMMON(dev); EventNotifier *n = &s->peers[s->vm_id].eventfds[vector]; + MSIVector *v = &s->msi_vectors[vector]; int ret; IVSHMEM_DPRINTF("vector mask %p %d\n", dev, vector); + if (!v->pdev) { + error_report("ivshmem: vector %d route does not exist", vector); + return; + } - ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n, - s->msi_vectors[vector].virq); + ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n, v->virq); if (ret != 0) { error_report("remove_irqfd_notifier_gsi failed"); }