From nobody Fri Apr 19 21:15:46 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1593426547; cv=none; d=zohomail.com; s=zohoarc; b=hZgHzFN08U04uBWmO8hjKIxegAfgbbEW8zzPxVy6pwBt+3Ze3QHf4VNVjpTybLbYPE9H4tpQOcpu3KZS/ReVLucOSW9j8em1o7sqdcx910tT6O6GGI9j1ToF5bifJ2c+SN6BXa8M0VHr18oU3EQjD4WtkrpF6+ODOWYhOmUE2bc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1593426547; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To; bh=7yp9Pp7XDgkJ4ho5kgEceyuB1D+3HS7nf67xkIsI1gc=; b=HXxGVvFAL+C6Ux+TxE/BPn33VPcUu2Dkk1qQ3fhcmToTMY3ZI+YSAktNLql8hcwMKJMz4ConZvwtqqojPC/FiBrue5lRS1OIesEC7UD/lqliHNAIwwiboCLFCFi7uqGVg8jf0U4foUgY2XiwPL4jvN717UHTrGw/4z6RS0iZHkA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1593426547579343.91466312559305; Mon, 29 Jun 2020 03:29:07 -0700 (PDT) Received: from localhost ([::1]:33744 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jpr2A-0007Cl-FN for importer@patchew.org; Mon, 29 Jun 2020 06:29:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60158) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jpr1M-0006Ya-Id for qemu-devel@nongnu.org; Mon, 29 Jun 2020 06:28:16 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:40460 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jpr1J-0000KO-OV for qemu-devel@nongnu.org; Mon, 29 Jun 2020 06:28:15 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-165-zkfaIPz5MyCJ6Pec_doHlQ-1; Mon, 29 Jun 2020 06:28:09 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2C5E4BFCF for ; Mon, 29 Jun 2020 10:28:08 +0000 (UTC) Received: from localhost (ovpn-113-61.ams2.redhat.com [10.36.113.61]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2E9CB5D9CD; Mon, 29 Jun 2020 10:28:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593426490; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7yp9Pp7XDgkJ4ho5kgEceyuB1D+3HS7nf67xkIsI1gc=; b=ONFDSRo+lfHF66GX2OjTpt0u8v7BVnaiHMbz2oB2KAihIEk6bfMGQBVb73tzCqFnyRH912 pG1U9pF68v26j7vntdR4m8H1GqQEX8igdAKF2pCffHktwO4Dem9HWtO7CE4jCOgGVAb/pJ gUYxDixZK7fOwGtKQmyucMwXkmQASd8= X-MC-Unique: zkfaIPz5MyCJ6Pec_doHlQ-1 From: Cornelia Huck To: "Dr. David Alan Gilbert" , Stefan Hajnoczi , "Michael S. Tsirkin" Subject: [PATCH RFC] virtio-fs: force virtio 1.x usage Date: Mon, 29 Jun 2020 12:27:58 +0200 Message-Id: <20200629102758.421552-1-cohuck@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=207.211.31.81; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/29 01:03:51 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Cornelia Huck , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" virtio-fs devices are only specified for virtio-1, so it is unclear how a legacy or transitional device should behave. Signed-off-by: Cornelia Huck --- Forcing off legacy now (after the virtio-fs device has already been available) may have unintended consequences, therefore RFC. By default, a virtio-pci device uses 'AUTO' for disable_legacy, which will resolve to different values based upon which bus the device has been plugged. Therefore, forcing disable_legacy may result in the same device or a quite different one. Even though pre-virtio-1 behaviour of virtio-fs devices is simply not specified, toggling disable_legacy will have implications for the BAR layout, IIRC, and therefore a guest might end up getting a different device, even if it always used it with virtio-1 anyway. Not sure what the best way to solve this problem is. Adding a compat property for disable_legacy=3DAUTO may be the right thing to do, but I'm not quite clear if there are any further implications here. Whatever we do here, we should make sure that the ccw incarnation of this device indeed forces virtio-1. --- hw/virtio/vhost-user-fs-pci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/virtio/vhost-user-fs-pci.c b/hw/virtio/vhost-user-fs-pci.c index e11c889d82b3..244205edf765 100644 --- a/hw/virtio/vhost-user-fs-pci.c +++ b/hw/virtio/vhost-user-fs-pci.c @@ -44,6 +44,7 @@ static void vhost_user_fs_pci_realize(VirtIOPCIProxy *vpc= i_dev, Error **errp) vpci_dev->nvectors =3D dev->vdev.conf.num_request_queues + 2; } =20 + virtio_pci_force_virtio_1(vpci_dev); qdev_realize(vdev, BUS(&vpci_dev->bus), errp); } =20 --=20 2.25.4