On 2013-09-16 16:06, Paolo Bonzini wrote: > Remove the useless argument, and do not do anything if there are no > VMs running at the time of the hotplug. kvm_cpu_hotplug already filters !kvm_usage_count. If we need the check to be under kvm_lock, drop that line as well. If that is not required (machine still halted?), drop the related changes here. Jan > > Cc: stable@xxxxxxxxxxxxxxx > Cc: kvm@xxxxxxxxxxxxxxx > Cc: gleb@xxxxxxxxxx > Cc: jan.kiszka@xxxxxxxxxxx > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > --- > virt/kvm/kvm_main.c | 14 ++++++++------ > 1 file changed, 8 insertions(+), 6 deletions(-) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 979bff4..75522b3 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -2681,10 +2681,11 @@ static void hardware_enable_nolock(void *junk) > } > } > > -static void hardware_enable(void *junk) > +static void hardware_enable(void) > { > raw_spin_lock(&kvm_lock); > - hardware_enable_nolock(junk); > + if (kvm_usage_count) > + hardware_enable_nolock(NULL); > raw_spin_unlock(&kvm_lock); > } > > @@ -2698,10 +2699,11 @@ static void hardware_disable_nolock(void *junk) > kvm_arch_hardware_disable(NULL); > } > > -static void hardware_disable(void *junk) > +static void hardware_disable(void) > { > raw_spin_lock(&kvm_lock); > - hardware_disable_nolock(junk); > + if (kvm_usage_count) > + hardware_disable_nolock(NULL); > raw_spin_unlock(&kvm_lock); > } > > @@ -2756,12 +2758,12 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val, > case CPU_DYING: > printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n", > cpu); > - hardware_disable(NULL); > + hardware_disable(); > break; > case CPU_STARTING: > printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n", > cpu); > - hardware_enable(NULL); > + hardware_enable(); > break; > } > return NOTIFY_OK; > -- Siemens AG, Corporate Technology, CT RTC ITP SES-DE Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html