From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36211) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zj8Hu-0005di-7H for qemu-devel@nongnu.org; Mon, 05 Oct 2015 12:06:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zj8Hq-0005sX-79 for qemu-devel@nongnu.org; Mon, 05 Oct 2015 12:06:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45654) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zj8Hq-0005sE-1Z for qemu-devel@nongnu.org; Mon, 05 Oct 2015 12:06:50 -0400 From: Eduardo Habkost Date: Mon, 5 Oct 2015 13:06:24 -0300 Message-Id: <1444061194-32753-3-git-send-email-ehabkost@redhat.com> In-Reply-To: <1444061194-32753-1-git-send-email-ehabkost@redhat.com> References: <1444061194-32753-1-git-send-email-ehabkost@redhat.com> Subject: [Qemu-devel] [PULL 02/12] vl: Add another sanity check to smp_parse() function List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: qemu-devel@nongnu.org, Paolo Bonzini , Thomas Huth , =?UTF-8?q?Andreas=20F=C3=A4rber?= , Richard Henderson From: Thomas Huth The code in smp_parse already checks the topology information for sockets * cores * threads < cpus and bails out with an error in that case. However, it is still possible to supply a bad configuration the other way round, e.g. with: qemu-system-xxx -smp 4,sockets=1,cores=4,threads=2 QEMU then still starts the guest, with topology configuration that is rather incomprehensible and likely not what the user wanted. So let's add another check to refuse such wrong configurations. Signed-off-by: Thomas Huth Reviewed-by: Eduardo Habkost Acked-by: Cornelia Huck Acked-by: Bastian Koppelmann Signed-off-by: Eduardo Habkost --- vl.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/vl.c b/vl.c index 8d1846c..f2bd8d2 100644 --- a/vl.c +++ b/vl.c @@ -1223,7 +1223,13 @@ static void smp_parse(QemuOpts *opts) exit(1); } - max_cpus = qemu_opt_get_number(opts, "maxcpus", 0); + max_cpus = qemu_opt_get_number(opts, "maxcpus", cpus); + if (sockets * cores * threads > max_cpus) { + fprintf(stderr, "cpu topology: error: " + "sockets (%u) * cores (%u) * threads (%u) > maxcpus (%u)\n", + sockets, cores, threads, max_cpus); + exit(1); + } smp_cpus = cpus; smp_cores = cores > 0 ? cores : 1; -- 2.1.0