From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [uq/master patch 1/2] kvm-all.c: use recommended max vcpus limit Date: Sun, 18 Aug 2013 13:15:12 -0300 Message-ID: <20130818161512.GA7951@amt.cnet> References: <20130812195629.350634011@redhat.com> <20130812195730.079414823@redhat.com> <5210E81C.7030109@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org, gleb@redhat.com To: Paolo Bonzini Return-path: Received: from mx1.redhat.com ([209.132.183.28]:21088 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753597Ab3HRQPc (ORCPT ); Sun, 18 Aug 2013 12:15:32 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r7IGFVRm016387 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 18 Aug 2013 12:15:31 -0400 Content-Disposition: inline In-Reply-To: <5210E81C.7030109@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Sun, Aug 18, 2013 at 05:28:28PM +0200, Paolo Bonzini wrote: > Il 12/08/2013 21:56, Marcelo Tosatti ha scritto: > > Commit 8c3ba334f8588e1d5099f8602cf01897720e0eca, "KVM: x86: Raise the > > hard VCPU count limit", upstream introduced the notion of a recommended > > vcpu max limit. > > > > Switch the order so the recommended vcpu max limit is used instead of > > the actual max vcpu limit. > > > > Signed-off-by: Marcelo Tosatti > > > > Index: qemu/kvm-all.c > > =================================================================== > > --- qemu.orig/kvm-all.c > > +++ qemu/kvm-all.c > > @@ -1321,11 +1321,11 @@ static int kvm_max_vcpus(KVMState *s) > > * procedure from the kernel API documentation to cope with > > * older kernels that may be missing capabilities. > > */ > > - ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS); > > + ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS); > > if (ret) { > > return ret; > > } > > - ret = kvm_check_extension(s, KVM_CAP_NR_VCPUS); > > + ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS); > > if (ret) { > > return ret; > > } > > > > > > This would break "working" configurations. Perhaps we should just warn > if the VCPU limit exceeds KVM_CAP_NR_VCPUS, and fail if the VCPU limit > exceeds KVM_CAP_MAX_VCPUS. > > Patch 2 is fine, ok to apply it (since it fixes a real bug) and then you > can work on top of it? OK, please apply patch 2.