When testing CPU hotplug, I found cpu can't be onlined with kvm enabled
sometimes. The reason is smp_call_function_single is a nop if the thread
is running on the target cpu. I think CPU_ONLINE case doesn't require
the fix as the online CPU isn't plugged into sheduler yet.
Signed-off-by: Shaohua Li <[EMAIL PROTECTED]>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index dc7a8c7..806a931 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -2360,6 +2360,7 @@ static int kvm_cpu_hotplug(struct notifier_block
*notifier, unsigned long val,
void *v)
{
int cpu = (long)v;
+ int this_cpu;
switch (val) {
case CPU_DOWN_PREPARE:
@@ -2367,8 +2368,13 @@ static int kvm_cpu_hotplug(struct notifier_block
*notifier, unsigned long val,
printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
cpu);
decache_vcpus_on_cpu(cpu);
- smp_call_function_single(cpu, kvm_arch_ops->hardware_disable,
- NULL, 0, 1);
+ this_cpu = get_cpu();
+ if (this_cpu == cpu)
+ kvm_arch_ops->hardware_disable(NULL);
+ else
+ smp_call_function_single(cpu,
+ kvm_arch_ops->hardware_disable, NULL, 0, 1);
+ put_cpu();
break;
case CPU_ONLINE:
printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
kvm-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/kvm-devel
