From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751793AbeCZIpO convert rfc822-to-8bit (ORCPT ); Mon, 26 Mar 2018 04:45:14 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57728 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750983AbeCZIpC (ORCPT ); Mon, 26 Mar 2018 04:45:02 -0400 Date: Mon, 26 Mar 2018 10:44:55 +0200 From: Cornelia Huck To: Pierre Morel Cc: Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com Subject: Re: [PATCH v3 01/14] KVM: s390: refactor crypto initialization Message-ID: <20180326104455.7773be7b.cohuck@redhat.com> In-Reply-To: <3227b02e-4a16-295d-9a01-043702cf149d@linux.vnet.ibm.com> References: <1521051954-25715-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1521051954-25715-2-git-send-email-akrowiak@linux.vnet.ibm.com> <3227b02e-4a16-295d-9a01-043702cf149d@linux.vnet.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 15 Mar 2018 15:55:39 +0100 Pierre Morel wrote: > On 15/03/2018 15:48, Tony Krowiak wrote: > > On 03/15/2018 08:26 AM, Pierre Morel wrote: > >> On 14/03/2018 19:25, Tony Krowiak wrote: > >>> diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig > >>> index a3dbd45..4ca9077 100644 > >>> --- a/arch/s390/kvm/Kconfig > >>> +++ b/arch/s390/kvm/Kconfig > >>> @@ -33,6 +33,7 @@ config KVM > >>>       select HAVE_KVM_INVALID_WAKEUPS > >>>       select SRCU > >>>       select KVM_VFIO > >>> +    select ZCRYPT > >> > >> I do not think it is a good solution to *always* enable ZCRYPT > >> when we have KVM. > > If CONFIG_ZCRYPT is not selected, then the kvm_ap_apxa_installed() > > function will not compile > > because it calls a zcrypt interface. How would you suggest we make > > sure zcrypt interfaces > > used in KVM are built if CONFIG_ZCRYPT is not selected? > > if zcrypt is not configured, I suppose that the KVM code initializaing CRYCB > has no use but the function will be called from KVM. > So I would do something like: > > #ifdef ZCRYPT > external definitions. > #else > stubs returning error -ENOZCRYPT (or whatever) > #endif The kvm code used some kind of detection for crycb before (IIRC it was for the key-wrapping stuff). I assume that usage is independent of zcrypt driver usage in the host? So, I think that apxa detection function should be used to s390 architecture base code and not be conditional on anything.