From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] vfio: Enable VFIO device for powerpc Date: Mon, 7 Sep 2015 13:06:41 +0200 Message-ID: <55ED6FC1.60205@redhat.com> References: <1439428546-13416-1-git-send-email-david@gibson.dropbear.id.au> <55DD8822.4060409@suse.de> <20150826185442.GB2662@fergus.ozlabs.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: David Gibson , alex.williamson@redhat.com, aik@ozlabs.ru, mdroth@linux.vnet.ibm.com, benh@kernel.crashing.org, mpe@ellerman.id.au, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kvm-ppc To: Paul Mackerras , Alexander Graf Return-path: In-Reply-To: <20150826185442.GB2662@fergus.ozlabs.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 26/08/2015 20:54, Paul Mackerras wrote: > On Wed, Aug 26, 2015 at 11:34:26AM +0200, Alexander Graf wrote: >> >> >> On 13.08.15 03:15, David Gibson wrote: >>> ec53500f "kvm: Add VFIO device" added a special KVM pseudo-device which is >>> used to handle any necessary interactions between KVM and VFIO. >>> >>> Currently that device is built on x86 and ARM, but not powerpc, although >>> powerpc does support both KVM and VFIO. This makes things awkward in >>> userspace >>> >>> Currently qemu prints an alarming error message if you attempt to use VFIO >>> and it can't initialize the KVM VFIO device. We don't want to remove the >>> warning, because lack of the KVM VFIO device could mean coherency problems >>> on x86. On powerpc, however, the error is harmless but looks disturbing, >>> and a test based on host architecture in qemu would be ugly, and break if >>> we do need the KVM VFIO device for something important in future. >>> >>> There's nothing preventing the KVM VFIO device from being built for >>> powerpc, so this patch turns it on. It won't actually do anything, since >>> we don't define any of the arch_*() hooks, but it will make qemu happy and >>> we can extend it in future if we need to. >>> >>> Signed-off-by: David Gibson >>> Reviewed-by: Eric Auger >> >> Paul is going to take care of the kvm-ppc tree for 4.3. Also, ppc kvm >> patches should get CC on the kvm-ppc@vger mailing list ;). >> >> Paul, could you please pick this one up? > > Sure, I'll do that once I get home (end of this week). This was not in the 4.3 pull request, but I think we can apply it after the end of the merge window. Paolo