From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A35B5C433DB for ; Tue, 16 Feb 2021 11:52:43 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2CF7064DA5 for ; Tue, 16 Feb 2021 11:52:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2CF7064DA5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:58238 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lByuI-00035j-8D for qemu-devel@archiver.kernel.org; Tue, 16 Feb 2021 06:52:42 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42136) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lBytg-0002fu-Gb for qemu-devel@nongnu.org; Tue, 16 Feb 2021 06:52:04 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:31533) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lBytf-0001SJ-3Y for qemu-devel@nongnu.org; Tue, 16 Feb 2021 06:52:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613476322; 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: in-reply-to:in-reply-to:references:references; bh=CgLnDCnoZwgqvOROCHOsMIbY+Gn/cI5oI0ov7soiR8Y=; b=Lc4r2TH4zIAQMX/HxgwLMknDOPAOeArwKy0ZbPT6r8LlF2vPURbmBXKfCeAeuMalY/C251 bJb6eS5Xu+Joy1P4jJSxQiWonws63o98EpQ77NsGkboyuEwhpvXQbzha689i48OJXILII/ AvrsDFHsHeFv5CJyscXZiQ25ozVr7RY= 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-518-rq2xS1_mOeWWzWXu6qt24w-1; Tue, 16 Feb 2021 06:51:58 -0500 X-MC-Unique: rq2xS1_mOeWWzWXu6qt24w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 13AF580403B; Tue, 16 Feb 2021 11:51:57 +0000 (UTC) Received: from gondolin (ovpn-113-145.ams2.redhat.com [10.36.113.145]) by smtp.corp.redhat.com (Postfix) with ESMTP id AB34A1002382; Tue, 16 Feb 2021 11:51:52 +0000 (UTC) Date: Tue, 16 Feb 2021 12:51:50 +0100 From: Cornelia Huck To: "Michael S. Tsirkin" Subject: Re: [PATCH] virtio-ccw: commands on revision-less devices Message-ID: <20210216125150.5cce488d.cohuck@redhat.com> In-Reply-To: <20210216064013-mutt-send-email-mst@kernel.org> References: <20210216111830.1087847-1-cohuck@redhat.com> <20210216064013-mutt-send-email-mst@kernel.org> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=cohuck@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no 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: Halil Pasic , Christian Borntraeger , Thomas Huth , qemu-s390x@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 16 Feb 2021 06:40:41 -0500 "Michael S. Tsirkin" wrote: > On Tue, Feb 16, 2021 at 12:18:30PM +0100, Cornelia Huck wrote: > > The virtio standard specifies that any non-transitional device must > > reject commands prior to revision setting (which we do) and else > > assume revision 0 (legacy) if the driver sends a non-revision-setting > > command first. We neglected to do the latter. > > > > Fortunately, nearly everything worked as intended anyway; the only > > problem was not properly rejecting revision setting after some other > > command had been issued. Easy to fix by setting revision to 0 if > > we see a non-revision command on a legacy-capable revision-less > > device. > > > > Signed-off-by: Cornelia Huck > > Reviewed-by: Michael S. Tsirkin > > Feel free to merge. > > Curious how was this discovered. Code reading :) I have not seen any errors in the wild.