From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] zcrypt: handle AP Info notification from CHSC SEI command References: <1548870526-30595-1-git-send-email-akrowiak@linux.ibm.com> <88b72363-9dca-4653-c326-9c37b6349a32@linux.ibm.com> <20190201090159.GC3770@osiris> From: Tony Krowiak Date: Fri, 1 Feb 2019 10:38:32 -0500 MIME-Version: 1.0 In-Reply-To: <20190201090159.GC3770@osiris> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Message-Id: Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Heiko Carstens Cc: Sebastian Ott , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Martin Schwidefsky , oberpar@linux.ibm.com, freude@linux.ibm.com, pmorel@linux.ibm.com, pasic@linux.ibm.com, cohuck@redhat.com List-ID: On 2/1/19 4:01 AM, Heiko Carstens wrote: > On Thu, Jan 31, 2019 at 06:28:39PM -0500, Tony Krowiak wrote: >> On 1/30/19 1:32 PM, Sebastian Ott wrote: >>> On Wed, 30 Jan 2019, Tony Krowiak wrote: >>>> +#if IS_ENABLED(CONFIG_ZCRYPT) >>>> +void ap_bus_cfg_chg(void); >>>> +#else >>>> +#error "no CONFIG_ZCRYPT" >>> ^ >>> I don't think that's the right thing to do here. >> >> I'd like to leave it. If somebody edits .config >> and sets CONFIG_ZCRYPT=n, then the build will >> fail. The preprocessor error above tells them >> why. > > No, the kernel build should never fail if a config option is not set. > Also the above should be "#ifdef CONFIG_ZCRYPT". Will do. > > In addition (this isn't quoted unfortunately) the alternative function > in the header file is missing the "inline" attribute. Can you please > add that too? I can. > > static inline void ap_bus_cfg_chg(void) { } > >>>> +* A config change has happened, Force an ap bus rescan. >>>> +*/ >>>> +void ap_bus_cfg_chg(void) >>>> +{ >>>> + AP_DBF(DBF_INFO, "%s config change, forcing bus rescan\n", __func__); >>>> + >>>> + ap_bus_force_rescan(); >>>> +} >>>> +EXPORT_SYMBOL(ap_bus_cfg_chg); >>> >>> There is no need for the export symbol - you don't call that function >> >from module code. >>> As an unrelated question, just to be sure: ap_bus.c is compiled as >>> built-in even with ZCRYPT=m, right? >> >> No. If you edit .config and set CONFIG_ZCRYPT=m, ap_bus.c will be built >> into the zcrypt.ko module. Through some other magic, the zcrypt module >> is loaded when linux boots. > > If that happens, then we have a build problem that needs to be > fixed. What exactly are you doing to get the ap code linked into the > zcrypt module? To tell you the truth, I don't know. The build configuration precedes my creating this patch by many years. I only discovered these anomalies by playing with the CONFIG_ZCRYPT option in response to Sebastian's comments. I will have to take this up with our internal IBM maintainer. >