From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754372AbeENPBm (ORCPT ); Mon, 14 May 2018 11:01:42 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59180 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752379AbeENPBj (ORCPT ); Mon, 14 May 2018 11:01:39 -0400 Date: Mon, 14 May 2018 17:01:35 +0200 From: Cornelia Huck To: Halil Pasic Cc: Dong Jia Shi , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH 1/1] s390: vfio-ccw: push down unsupported IDA check Message-ID: <20180514170135.2cab4f7d.cohuck@redhat.com> In-Reply-To: <7bd8fc8b-0500-9905-a3a0-2ec56d3fc9f2@linux.ibm.com> References: <20180509173647.61367-1-pasic@linux.ibm.com> <20180514135554.29569999.cohuck@redhat.com> <20180514160016.3b689728.cohuck@redhat.com> <7bd8fc8b-0500-9905-a3a0-2ec56d3fc9f2@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 14 May 2018 16:44:29 +0200 Halil Pasic wrote: > On 05/14/2018 04:00 PM, Cornelia Huck wrote: > > On Mon, 14 May 2018 15:37:17 +0200 > > Halil Pasic wrote: > > > >> On 05/14/2018 01:55 PM, Cornelia Huck wrote: > >>> On Wed, 9 May 2018 19:36:47 +0200 > >>> Halil Pasic wrote: > >>> > >>>> + /* > >>>> + * 2k byte block IDAWs (fmt1 or fmt2) are not yet supported. > >>>> + * There are however CPs that don't use IDA at all, and can > >>>> + * benefit from not failing until failure is eminent. > >>> > >>> What about: > >>> > >>> "As we don't want to fail direct addressing even if the orb specified > >>> one of the unsupported formats, we defer checking for IDAWs in > >>> unsupported formats to here." > >> > >> Was the second sentence only confusing because of CP? I'm not perfectly > >> satisfied with your version either: > >> * 'fail direct addressing even if the orb specified one of the unsupported formats' > >> I wanted to say: 'hey it does not matter what format for IDA the orb implies > >> if the channel program does not use any IDA at all'. That could be paraphrased > >> as channel programs using direct addressing exclusively. But failing the direct > >> addressing does not fit for me. > > > > But that's effectively what happens now, no? We reject the orb out of > > hand due to unsupported flags that do not have any relevance for the > > channel program in that case. > > Yes, that's what happens now, except that we make the whole channel program fail, > and not the direct addressing. But the comment should describe what happens > with the patch applied. Even more, it should describe _why_ it is done that way (the reason being "we don't want to fail..."). That's where I've been coming from. > >>> The patch looks sane, I have only issues with the description/comments. > >>> > >> > >> Thanks for having a look. Please give me short feedback about the one > >> open point and I will respin with the requested changes. > > > > Does anybody else have feedback? > > > > Will wait a day or so. Dong Jia and Jason have already seen the patch, and > they only complained about the text. Since that spin was mainly for the > tested-by tags, and I stated that any substantial discussion should happen > upstream, I ignored those complaints. > > So yes I will wait a bit so everybody can chime in. Sounds good.