[Xen-changelog] [xen-unstable] xen: add assertion in default_vcpu0_location to protect against broken masks

[Xen patchbot-unstable <patchbot@xxxxxxx>]

# HG changeset patch
# User Ian Campbell <ian.campbell@xxxxxxxxxx>
# Date 1341309153 -3600
# Node ID 1b3198c8f140918574ccfe6baba92ef214d69c1a
# Parent  46b201f42bf850e7d9a4cbef8fad59798898fabc
xen: add assertion in default_vcpu0_location to protect against broken masks

When setting up the cpu sibling/etc masks on ARM I accidentally and
incorrectly omitted a CPU from it's own sibling mask which caused this
function to return an invalid cpu number which caused errors later when we
tried to access per_cpu data for that invalid cpu.

Add an assert to catch this in the future.

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
Acked-by: Keir Fraser <keir@xxxxxxx>
Committed-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
---


diff -r 46b201f42bf8 -r 1b3198c8f140 xen/common/domctl.c
--- a/xen/common/domctl.c       Tue Jul 03 10:52:32 2012 +0100
+++ b/xen/common/domctl.c       Tue Jul 03 10:52:33 2012 +0100
@@ -192,6 +192,7 @@ static unsigned int default_vcpu0_locati
     cpu = cpumask_first(&cpu_exclude_map);
     if ( cpumask_weight(&cpu_exclude_map) > 1 )
         cpu = cpumask_next(cpu, &cpu_exclude_map);
+    ASSERT(cpu < nr_cpu_ids);
     for_each_cpu(i, online)
     {
         if ( cpumask_test_cpu(i, &cpu_exclude_map) )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog