From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Borntraeger Subject: RFC: s390: extension capability for new address space layout Date: Tue, 20 Sep 2011 13:56:42 +0200 Message-ID: <4E787F7A.2070600@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Alexander Graf , Heiko Carstens , Carsten Otte , KVM list , Martin Schwidefsky To: Avi Kivity , Marcelo Tosatti Return-path: Received: from mtagate2.uk.ibm.com ([194.196.100.162]:53825 "EHLO mtagate2.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730Ab1ITL4p (ORCPT ); Tue, 20 Sep 2011 07:56:45 -0400 Received: from d06nrmr1806.portsmouth.uk.ibm.com (d06nrmr1806.portsmouth.uk.ibm.com [9.149.39.193]) by mtagate2.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p8KBui6p012280 for ; Tue, 20 Sep 2011 11:56:44 GMT Received: from d06av02.portsmouth.uk.ibm.com (d06av02.portsmouth.uk.ibm.com [9.149.37.228]) by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p8KBuhwx2162864 for ; Tue, 20 Sep 2011 12:56:43 +0100 Received: from d06av02.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av02.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p8KBuhNv023923 for ; Tue, 20 Sep 2011 05:56:43 -0600 Sender: kvm-owner@vger.kernel.org List-ID: Avi,Marcelo, 598841ca9919d008b520114d8a4378c4ce4e40a1 ([S390] use gmap address spaces for kvm guest images) changed kvm on s390 to use a separate address space for kvm guests. We can now put KVM guests anywhere in the user address mode with a size up to 8PB - as long as the memory is 1MB-aligned. This change was done without KVM extension capability bit. The change was added after 3.0, but we still have a chance to add a feature bit before 3.1 (keeping the releases in a sane state). Can you have a look at the change below and give you ACK or NACK? If ok, I would push this patch to Heiko to be submitted via the s390 stream for 3.1. Christian Signed-off-by: Christian Borntraeger --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -123,6 +123,7 @@ int kvm_dev_ioctl_check_extension(long ext) switch (ext) { case KVM_CAP_S390_PSW: + case KVM_CAP_S390_GMAP: r = 1; break; default: diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 2c366b5..b2e9cc1 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -553,6 +553,7 @@ struct kvm_ppc_pvinfo { #define KVM_CAP_SPAPR_TCE 63 #define KVM_CAP_PPC_SMT 64 #define KVM_CAP_PPC_RMA 65 +#define KVM_CAP_S390_GMAP 66 #ifdef KVM_CAP_IRQ_ROUTING