From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754169AbbANSgm (ORCPT ); Wed, 14 Jan 2015 13:36:42 -0500 Received: from cantor2.suse.de ([195.135.220.15]:36354 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754099AbbANSgk (ORCPT ); Wed, 14 Jan 2015 13:36:40 -0500 Date: Wed, 14 Jan 2015 19:36:36 +0100 From: "Luis R. Rodriguez" To: Stefano Stabellini Cc: "Luis R. Rodriguez" , hpa@zytor.com, josh@joshtriplett.org, sam@ravnborg.org, Michal Marek , Randy Dunlap , Ian Campbell , kvm@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, mtosatti@redhat.com, Pekka Enberg , fengguang.wu@intel.com, levinsasha928@gmail.com, David Rientjes , xen-devel@lists.xenproject.org, Borislav Petkov , David Vrabel , bpoirier@suse.de Subject: Re: [Xen-devel] [PATCH v2 2/2] x86, arm, platform, xen, kconfig: add xen defconfig helper Message-ID: <20150114183636.GG27566@wotan.suse.de> References: <1418168138-6425-1-git-send-email-mcgrof@do-not-panic.com> <1418168138-6425-3-git-send-email-mcgrof@do-not-panic.com> <20150113192617.GC27566@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 14, 2015 at 11:29:41AM +0000, Stefano Stabellini wrote: > On Tue, 13 Jan 2015, Luis R. Rodriguez wrote: > > On Mon, Dec 15, 2014 at 02:58:26PM +0000, Stefano Stabellini wrote: > > > On Tue, 9 Dec 2014, Luis R. Rodriguez wrote: > > > > From: "Luis R. Rodriguez" > > > > > > > > This lets you build a kernel which can support xen dom0 > > > > or xen guests by just using: > > > > > > > > make xenconfig > > > > > > > > on both x86 and arm64 kernels. This also splits out the > > > > options which are available currently to be built with x86 > > > > and 'make ARCH=arm64' under a shared config. > > > > > > > > Technically xen supports a dom0 kernel and also a guest > > > > kernel configuration but upon review with the xen team > > > > since we don't have many dom0 options its best to just > > > > combine these two into one. > > > > > > > > Cc: Josh Triplett > > > > Cc: Borislav Petkov > > > > Cc: Pekka Enberg > > > > Cc: David Rientjes > > > > Cc: Michal Marek > > > > Cc: Randy Dunlap > > > > Cc: penberg@kernel.org > > > > Cc: levinsasha928@gmail.com > > > > Cc: mtosatti@redhat.com > > > > Cc: fengguang.wu@intel.com > > > > Cc: David Vrabel > > > > Cc: Ian Campbell > > > > Cc: Konrad Rzeszutek Wilk > > > > Cc: xen-devel@lists.xenproject.org > > > > Reviewed-by: Josh Triplett > > > > Signed-off-by: Luis R. Rodriguez > > > > --- > > > > arch/x86/configs/xen.config | 7 +++++++ > > > > kernel/configs/xen.config | 30 ++++++++++++++++++++++++++++++ > > > > scripts/kconfig/Makefile | 5 +++++ > > > > 3 files changed, 42 insertions(+) > > > > create mode 100644 arch/x86/configs/xen.config > > > > create mode 100644 kernel/configs/xen.config > > > > > > > > diff --git a/arch/x86/configs/xen.config b/arch/x86/configs/xen.config > > > > new file mode 100644 > > > > index 0000000..92b8587f > > > > --- /dev/null > > > > +++ b/arch/x86/configs/xen.config > > > > @@ -0,0 +1,7 @@ > > > > +# x86 xen specific config options > > > > +CONFIG_XEN_PVHVM=y > > > > +CONFIG_XEN_MAX_DOMAIN_MEMORY=500 > > > > +CONFIG_XEN_SAVE_RESTORE=y > > > > +# CONFIG_XEN_DEBUG_FS is not set > > > > +CONFIG_XEN_PVH=y > > > > +CONFIG_XEN_MCE_LOG=y > > > > diff --git a/kernel/configs/xen.config b/kernel/configs/xen.config > > > > new file mode 100644 > > > > index 0000000..d2ec010 > > > > --- /dev/null > > > > +++ b/kernel/configs/xen.config > > > > @@ -0,0 +1,30 @@ > > > > +# generic config > > > > +CONFIG_XEN=y > > > > +CONFIG_XEN_DOM0=y > > > > +CONFIG_PCI_XEN=y > > > > > > This shouldn't be here > > > > If PCI is not supported on the arch this won't be selected as kconfig would not > > allow for it, what would be the issue of keeping it here? > > It looks wrong to me to have an arch specific option here. Moreover many > ARM boards don't even have PCI, so it looks even worse. > CONFIG_PCI_XEN is certainly not a generic config option for Xen. OK fair enough. > > What xen instances > > would we not want to have this enabled for and can we instead manage that > > through Kconfig magic by negating PCI_XEN for it? > > Everything can be fixed via Kconfig magic, the point of this exercise is > to try to avoid it. > > Are there any cases on x86 where you don't actually want CONFIG_PCI_XEN? Not that I can think of. > If not, then why don't just enable it automatically and silently if > CONFIG_PCI is selected? If we did that, we could avoid specifying it > here. CONFIG_PCI_XEN already depends depends on PCI && XEN so I think its safe to just put it in blindly for x86. > In any case, given that CONFIG_PCI_XEN is only defined on x86, I think > it should be in arch/x86/configs/xen.config. OK! Will respin. Luis