From: Eduardo Habkost <ehabkost@redhat.com>
Date: Fri, 19 Dec 2014 02:59:47 +0000 (-0200)
Subject: vl: Don't silently change topology when all -smp options were set
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=ec2cbbdd80463efd4bc81a9d1362a2acb3097a21;p=qmiga%2Fqemu.git

vl: Don't silently change topology when all -smp options were set

QEMU tries to change the "threads" option even if it was explicitly set
in the command-line, and it shouldn't do that.

The right thing to do when all options (cpus, sockets, cores, threds)
are explicitly set is to sanity check them and abort in case they don't
make sense (i.e. when sockets*cores*threads < cpus).

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/vl.c b/vl.c
index 95451b6af8..f6b24c4070 100644
--- a/vl.c
+++ b/vl.c
@@ -1173,8 +1173,14 @@ static void smp_parse(QemuOpts *opts)
         } else if (cores == 0) {
             threads = threads > 0 ? threads : 1;
             cores = cpus / (sockets * threads);
-        } else {
+        } else if (threads == 0) {
             threads = cpus / (cores * sockets);
+        } else if (sockets * cores * threads < cpus) {
+            fprintf(stderr, "cpu topology: error: "
+                    "sockets (%u) * cores (%u) * threads (%u) < "
+                    "smp_cpus (%u)\n",
+                    sockets, cores, threads, cpus);
+            exit(1);
         }
 
         max_cpus = qemu_opt_get_number(opts, "maxcpus", 0);