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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 6CA30C43331 for ; Tue, 24 Mar 2020 17:05:42 +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 32D52206F6 for ; Tue, 24 Mar 2020 17:05:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UBLoeyU1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 32D52206F6 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]:52368 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jGmzl-0003Du-Ar for qemu-devel@archiver.kernel.org; Tue, 24 Mar 2020 13:05:41 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53533) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jGmym-0002NU-8a for qemu-devel@nongnu.org; Tue, 24 Mar 2020 13:04:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jGmyl-0007NO-0B for qemu-devel@nongnu.org; Tue, 24 Mar 2020 13:04:40 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:21973) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jGmyk-0007Mo-S3 for qemu-devel@nongnu.org; Tue, 24 Mar 2020 13:04:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585069477; 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=vIPLDkB9laSjEZg127wtUKAaW1CNgYEqjyQrqydKWgE=; b=UBLoeyU1whg94Y6Jlk8xJ2rkNCabf3TgPnf6+4C+puZqMMfL8WIciSJWdlU5/EHXopoNzo y3Zx1UlrBiTwVWdxI1HHWFW9geQSIrkJMwn9Kd4WSSigJX3FHvLSFq/mcEOnu0HFRzoafz WOAQSjAF26i6QslO7kc5cF3S+1DG2As= 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-38-STW_N6h7M1ypyUURUPo8SA-1; Tue, 24 Mar 2020 13:04:36 -0400 X-MC-Unique: STW_N6h7M1ypyUURUPo8SA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 89342DBBC; Tue, 24 Mar 2020 17:04:34 +0000 (UTC) Received: from gondolin (ovpn-113-109.ams2.redhat.com [10.36.113.109]) by smtp.corp.redhat.com (Postfix) with ESMTP id 259ECBBBE5; Tue, 24 Mar 2020 17:04:32 +0000 (UTC) Date: Tue, 24 Mar 2020 18:04:30 +0100 From: Cornelia Huck To: Eric Farman Subject: Re: [RFC PATCH v2 1/7] vfio-ccw: Return IOINST_CC_NOT_OPERATIONAL for EIO Message-ID: <20200324180430.3597ca94.cohuck@redhat.com> In-Reply-To: <20200206214509.16434-2-farman@linux.ibm.com> References: <20200206214509.16434-1-farman@linux.ibm.com> <20200206214509.16434-2-farman@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 63.128.21.74 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 , Jason Herne , qemu-s390x@nongnu.org, Jared Rossi , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 6 Feb 2020 22:45:03 +0100 Eric Farman wrote: > From: Farhan Ali > > EIO is returned by vfio-ccw mediated device when the backing > host subchannel is not operational anymore. So return cc=3 > back to the guest, rather than returning a unit check. > This way the guest can take appropriate action such as > issue an 'stsch'. > > Signed-off-by: Farhan Ali > Signed-off-by: Eric Farman > --- > > Notes: > v1->v2: [EF] > - Add s-o-b > - [Seems the discussion on v1 centered on the return code > set in the kernel, rather than anything that needs to > change here, unless I've missed something.] I've stared at this and at the kernel code for some time again; and I'm not sure if "return -EIO == not operational" is even true. That said, I'm not sure a unit check is the right response, either. The only thing I'm sure about is that the kernel code needs some review of return codes and some documentation... > > hw/vfio/ccw.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c > index 50cc2ec75c..19144ecfc7 100644 > --- a/hw/vfio/ccw.c > +++ b/hw/vfio/ccw.c > @@ -114,6 +114,7 @@ again: > return IOINST_CC_BUSY; > case -ENODEV: > case -EACCES: > + case -EIO: > return IOINST_CC_NOT_OPERATIONAL; > case -EFAULT: > default: