From nobody Sat Apr 27 07:27:27 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com; dmarc=pass(p=none dis=none) header.from=redhat.com Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1535464190241138.32005099892535; Tue, 28 Aug 2018 06:49:50 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 590873082120; Tue, 28 Aug 2018 13:49:48 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 210C37F48A; Tue, 28 Aug 2018 13:49:48 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id C6CF44BB7F; Tue, 28 Aug 2018 13:49:47 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id w7SDmH2N025811 for ; Tue, 28 Aug 2018 09:48:17 -0400 Received: by smtp.corp.redhat.com (Postfix) id 67D0B10DCF44; Tue, 28 Aug 2018 13:48:17 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id AF1CC10EE6DE; Tue, 28 Aug 2018 13:48:14 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Date: Tue, 28 Aug 2018 15:48:13 +0200 Message-Id: <1535464093-3648-1-git-send-email-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-loop: libvir-list@redhat.com Cc: libvir-list@redhat.com, drjones@redhat.com, ehabkost@redhat.com Subject: [libvirt] [PATCH v4] vl.c deprecate incorrect CPUs topology X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Tue, 28 Aug 2018 13:49:49 +0000 (UTC) X-ZohoMail: RDMRC_0 RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" -smp [cpus],sockets/cores/threads[,maxcpus] should describe topology so that total number of logical CPUs [sockets * cores * threads] would be equal to [maxcpus], however historically we didn't have such check in QEMU and it is possible to start VM with an invalid topology. Deprecate invalid options combination so we can make sure that the topology VM started with is always correct in the future. Users with an invalid sockets/cores/threads/maxcpus values should fix their CLI to make sure that [sockets * cores * threads] =3D=3D [maxcpus] Signed-off-by: Igor Mammedov Reviewed-by: Andrew Jones --- v4: - missed dot comment, fix it with s/./,/ (Andrew Jones ) v3: - more spelling fixes (Andrew Jones ) - place deprecation check after (sockets * cores * threads > max_cpus) ch= eck (Eduardo Habkost ) v2: - spelling&&co fixes (Andrew Jones ) --- qemu-deprecated.texi | 11 +++++++++++ vl.c | 7 +++++++ 2 files changed, 18 insertions(+) diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi index 87212b6..094b4ca 100644 --- a/qemu-deprecated.texi +++ b/qemu-deprecated.texi @@ -159,6 +159,17 @@ The 'file' driver for drives is no longer appropriate = for character or host devices and will only accept regular files (S_IFREG). The correct driver for these file types is 'host_cdrom' or 'host_device' as appropriate. =20 +@subsection -smp X,[socket=3Da,core=3Db,thread=3Dc],maxcpus=3DY (since 3.1) + +CPU topology properties should describe whole machine topology including +possible CPUs, but historically it was possible to start QEMU with +an incorrect topology where + sockets * cores * threads >=3D X && X < maxcpus +which could lead to an incorrect topology enumeration by the guest. +Support for invalid topologies will be removed, the user must ensure +topologies described with -smp include all possible cpus, i.e. + sockets * cores * threads =3D=3D maxcpus + @section QEMU Machine Protocol (QMP) commands =20 @subsection block-dirty-bitmap-add "autoload" parameter (since 2.12.0) diff --git a/vl.c b/vl.c index 5ba06ad..7fd700e 100644 --- a/vl.c +++ b/vl.c @@ -1246,6 +1246,13 @@ static void smp_parse(QemuOpts *opts) exit(1); } =20 + if (sockets * cores * threads !=3D max_cpus) { + warn_report("Invalid CPU topology deprecated: " + "sockets (%u) * cores (%u) * threads (%u) " + "!=3D maxcpus (%u)", + sockets, cores, threads, max_cpus); + } + smp_cpus =3D cpus; smp_cores =3D cores; smp_threads =3D threads; --=20 2.7.4 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list