From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48015) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fsqxL-0002lA-24 for qemu-devel@nongnu.org; Thu, 23 Aug 2018 10:51:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fsqxI-00070W-A3 for qemu-devel@nongnu.org; Thu, 23 Aug 2018 10:51:26 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:40982 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fsqxG-0006zP-Fy for qemu-devel@nongnu.org; Thu, 23 Aug 2018 10:51:23 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BBBE140216E6 for ; Thu, 23 Aug 2018 14:51:21 +0000 (UTC) From: Igor Mammedov Date: Thu, 23 Aug 2018 16:51:17 +0200 Message-Id: <1535035877-219196-1-git-send-email-imammedo@redhat.com> Subject: [Qemu-devel] [PATCH] vl.c: make sure maxcpus matches topology to prevent migration failure List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: pbonzini@redhat.com, ehabkost@redhat.com, dgilbert@redhat.com Topology (threads*cores*sockets) must match maxcpus to be valid, otherwise we could start QEMU with invalid topology that throws a error on migration destination side, that should not be reachable: Source: -smp 8,maxcpus=64,cores=1,threads=8,sockets=1 // hotplug cpus upto maxcpus Destination: -smp 64,maxcpus=64,cores=1,threads=8,sockets=1 qemu: cpu topology: sockets (1) * cores (1) * threads (8) < smp_cpus (64) Signed-off-by: Igor Mammedov --- vl.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/vl.c b/vl.c index 16b913f..2b35e0c 100644 --- a/vl.c +++ b/vl.c @@ -1238,10 +1238,10 @@ static void smp_parse(QemuOpts *opts) exit(1); } - if (sockets * cores * threads > max_cpus) { + if (sockets * cores * threads != max_cpus) { error_report("cpu topology: " - "sockets (%u) * cores (%u) * threads (%u) > " - "maxcpus (%u)", + "sockets (%u) * cores (%u) * threads (%u) not equal to" + " maxcpus (%u)", sockets, cores, threads, max_cpus); exit(1); } -- 2.7.4