From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41355) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dXlDl-000810-2Y for qemu-devel@nongnu.org; Wed, 19 Jul 2017 05:24:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dXlDg-00067b-5t for qemu-devel@nongnu.org; Wed, 19 Jul 2017 05:24:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:7997) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dXlDf-00067H-Tj for qemu-devel@nongnu.org; Wed, 19 Jul 2017 05:24:36 -0400 Date: Wed, 19 Jul 2017 11:24:30 +0200 From: Cornelia Huck Message-ID: <20170719112430.432e66da@gondolin> In-Reply-To: <8eadfe2a-7923-6c10-287e-06ad9eaffead@linux.vnet.ibm.com> References: <20170718142455.32676-1-cohuck@redhat.com> <20170718142455.32676-5-cohuck@redhat.com> <5f8a2315-9224-f20c-7524-11f9a8ac8efd@de.ibm.com> <20170719100007.1071ce70@gondolin> <8eadfe2a-7923-6c10-287e-06ad9eaffead@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH RFC v2 4/9] s390x/pci: do not advertise pci on non-pci builds List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Yi Min Zhao Cc: Christian Borntraeger , thuth@redhat.com, pmorel@linux.vnet.ibm.com, qemu-devel@nongnu.org, agraf@suse.de On Wed, 19 Jul 2017 16:56:18 +0800 Yi Min Zhao wrote: > =E5=9C=A8 2017/7/19 =E4=B8=8B=E5=8D=884:00, Cornelia Huck =E5=86=99=E9=81= =93: > > On Tue, 18 Jul 2017 21:56:26 +0200 > > Christian Borntraeger wrote: > > =20 > >> On 07/18/2017 04:24 PM, Cornelia Huck wrote: =20 > >>> Only set the zpci and aen feature bits on builds that actually > >>> support pci. > >>> > >>> Signed-off-by: Cornelia Huck > >>> --- > >>> target/s390x/kvm.c | 2 ++ > >>> 1 file changed, 2 insertions(+) > >>> > >>> diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > >>> index 831492f9a2..880eccd58a 100644 > >>> --- a/target/s390x/kvm.c > >>> +++ b/target/s390x/kvm.c > >>> @@ -2685,8 +2685,10 @@ void kvm_s390_get_host_cpu_model(S390CPUModel = *model, Error **errp) > >>> } > >>> > >>> /* set zpci and aen facilities */ > >>> +#ifdef CONFIG_PCI > >>> set_bit(S390_FEAT_ZPCI, model->features); > >>> set_bit(S390_FEAT_ADAPTER_EVENT_NOTIFICATION, model->features); > >>> +#endif > >>> > >>> if (s390_known_cpu_type(cpu_type)) { > >>> /* we want the exact model, even if some features are missi= ng */ > >>> =20 > >> Not strictly necessary but do you also want to ifdef this > >> > >> kvm_vm_enable_cap(s, KVM_CAP_S390_AIS, 0); > >> > >> call? > >> > >> If not you could actually even allow AEN but not PCI for !CONFIG_PCI. = =20 > > I'm a bit unsure about the relationship of ais and aen with pci. I > > remember that only adapters for pci currently support suppression, > > although it could spread to other adapter types in the future. Not sure > > about aen. > > > > So I'd keep the ais enablement call, even though it won't have much of > > an effect as no pci adapters will be registered. > > > > As I don't quite remember what aen governed, I need to rely on your > > feedback here. > > > > =20 > My understanding is that zpci replies on aen. But aen could exist=20 > independently. > After all, there is other device type using aen. I think only wrapping=20 > zpci is > enough. Ah, was aen the indicator bits related support? If yes, I agree that we should only turn off zpci.