Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967649Ab3DRJqi (ORCPT ); Thu, 18 Apr 2013 05:46:38 -0400 Received: from mail.skyhub.de ([78.46.96.112]:59406 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966129Ab3DRJqg (ORCPT ); Thu, 18 Apr 2013 05:46:36 -0400 Date: Thu, 18 Apr 2013 11:46:29 +0200 From: Borislav Petkov To: Marcelo Tosatti Cc: Pekka Enberg , Ingo Molnar , "H. Peter Anvin" , Sasha Levin , Fengguang Wu , lkml , x86-ml , kvm@vger.kernel.org Subject: Re: [PATCH] x86: Add a Kconfig shortcut for a kvm-bootable kernel Message-ID: <20130418094629.GC21719@pd.tnic> References: <20130412181956.GA13099@pd.tnic> <516A7760.7030907@kernel.org> <20130414110320.GB20547@pd.tnic> <20130416161852.GH5332@pd.tnic> <20130417232507.GC31059@amt.cnet> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20130417232507.GC31059@amt.cnet> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3423 Lines: 110 On Wed, Apr 17, 2013 at 08:25:07PM -0300, Marcelo Tosatti wrote: > On Tue, Apr 16, 2013 at 06:18:52PM +0200, Borislav Petkov wrote: > > On Sun, Apr 14, 2013 at 01:03:20PM +0200, Borislav Petkov wrote: > > > On Sun, Apr 14, 2013 at 12:31:12PM +0300, Pekka Enberg wrote: > > > > I obviously support having something like this in mainline. I wonder > > > > though if we could just call this "default standalone KVM guest > > > > config" instead of emphasizing testing angle. > > > > > > /me nods agreeingly... > > > > > > And it should be unter HYPERVISOR_GUEST where the rest of this stuff > > > resides. Good point. > > > > Sanity check question: > > > > Why not add the select stuff, i.e. this: > > > > select NET > > select NETDEVICES > > select PCI > > select BLOCK > > select BLK_DEV > > select NETWORK_FILESYSTEMS > > select INET > > select EXPERIMENTAL > > select TTY > > select SERIAL_8250 > > select SERIAL_8250_CONSOLE > > select IP_PNP > > select IP_PNP_DHCP > > select BINFMT_ELF > > select PCI_MSI > > select HAVE_ARCH_KGDB > > select DEBUG_KERNEL > > select KGDB > > select KGDB_SERIAL_CONSOLE > > select VIRTUALIZATION > > select VIRTIO > > select VIRTIO_RING > > select VIRTIO_PCI > > select VIRTIO_BLK > > select VIRTIO_CONSOLE > > select VIRTIO_NET > > select 9P_FS > > select NET_9P > > select NET_9P_VIRTIO > > > > to the option below which we already have. It is in the same sense a KVM > > guest support deal. > > > > Hmm. > > > > KVM people, any objections? > > None, but please don't mix it with 'KVM_GUEST' flag below. > > Actually, what about adding kvm variants of the two files at > arch/x86/configs/ ? two files? > > > config KVM_GUEST > > bool "KVM Guest support (including kvmclock)" > > depends on PARAVIRT > > select PARAVIRT_CLOCK > > default y > > ---help--- > > This option enables various optimizations for running under the KVM > > hypervisor. It includes a paravirtualized clock, so that instead > > of relying on a PIT (or probably other) emulation by the > > underlying device model, the host provides the guest with > > timing infrastructure such as time of day, and system time Hmm, ok, maybe I wasn't clear enough. My proposal was to actually add all (or maybe not *all* of them, but most) those selects above to the KVM_GUEST config option. Because, you very probably want to select all that stuff above anyway if you want to build a kvm guest kernel, no? IOW, something which says "Enable KVM guest support" should enable all the stuff needed for that. Or do you want to keep the current CONFIG_KVM_GUEST separate for special stuff? And yes, Sasha's suggestion to have an additional CONFIG_KVM_GUEST_KERNEL_TESTING or so option which enables debug stuff for people who write patches for the kernel and want to quickly smoke-test it in kvm. Basically, I'm looking from the perspective of a kernel dev who would like to make an optimal use of kvm for testing kernels. Does that make more sense? Thanks. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/