KVM: Don't spin on virt instruction faults during reboot

Since vmx blocks INIT signals, we disable virtualization extensions during
reboot.  This leads to virtualization instructions faulting; we trap these
faults and spin while the reboot continues.

Unfortunately spinning on a non-preemptible kernel may block a task that
reboot depends on; this causes the reboot to hang.

Fix by skipping over the instruction and hoping for the best.

Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Avi Kivity 2010-12-02 17:52:50 +02:00
parent 4cc703100b
commit b7c4145ba2
2 changed files with 10 additions and 11 deletions

View file

@ -90,7 +90,8 @@ static void hardware_disable_all(void);
static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
static bool kvm_rebooting;
bool kvm_rebooting;
EXPORT_SYMBOL_GPL(kvm_rebooting);
static bool largepages_enabled = true;
@ -2171,18 +2172,12 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
}
asmlinkage void kvm_handle_fault_on_reboot(void)
asmlinkage void kvm_spurious_fault(void)
{
if (kvm_rebooting) {
/* spin while reset goes on */
local_irq_enable();
while (true)
cpu_relax();
}
/* Fault while not rebooting. We want the trace. */
BUG();
}
EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
EXPORT_SYMBOL_GPL(kvm_spurious_fault);
static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
void *v)