From mboxrd@z Thu Jan 1 00:00:00 1970 From: Halil Pasic Subject: Re: [PATCH v2 5/5] vfio: ccw: add traceponits for interesting error paths Date: Mon, 30 Apr 2018 18:51:54 +0200 Message-ID: <42c331bf-8ba1-7a67-5ec8-6bebcfad4ed7@linux.ibm.com> References: <20180423110113.59385-1-bjsdjshi@linux.vnet.ibm.com> <20180423110113.59385-6-bjsdjshi@linux.vnet.ibm.com> <20180427121353.4453bdc2.cohuck@redhat.com> <20180428055023.GS5428@bjsdjshi@linux.vnet.ibm.com> <20180430135153.1d108675.cohuck@redhat.com> <20180430170358.0ee6fe6a.cohuck@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180430170358.0ee6fe6a.cohuck@redhat.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Cornelia Huck Cc: Dong Jia Shi , Halil Pasic , linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, borntraeger@de.ibm.com, bjsdjshi@linux.ibm.com, pmorel@linux.ibm.com List-ID: On 04/30/2018 05:03 PM, Cornelia Huck wrote: >> I think the naming of this fctl thing is a bit cryptic, >> but if we don't see this as ABI I'm fine with it -- can be improved. >> What would be a better name? I was thinking along the lines accept_request. >> (Bad error code would mean that the request did not get accepted. Good >> code does not mean the requested function was performed successfully.) > I think fctl is fine (if you don't understand what 'fctl' is, you're > unlikely to understand it even if it were named differently.) > AFAIU this fctl is a bit more complicated than the normal fctl. But better let sleeping dogs lie. >> Also I think vfio_ccw_io_fctl with no zero error code would make sense >> as dev_warn. If I were an admin looking into a problem I would very much >> appreciate seeing something in the messages log (and not having to enable >> tracing first). This point seems to be a good one for high level 'request gone >> bad' kind of report. Opinions? > I'd also exclude -EOPNOTSUPP (as this also might happen with e.g. a halt/clear enabled user space, which probes availability of halt/clear support by giving it a try once (yes, I really want to post my patches this week.)) > I'm looking forward to the clear/halt. It hope it will help me understand the big vfio-ccw picture better. There are still dark spots, but I don't feel like doing something against this, as there is quite some activity going on here -- and I don't want to hamper the efforts by binding resources. Regards, Halil