intel_idle: Check cpu_idle_get_driver() for NULL before dereferencing it.

commit 3735d524da64b70b41c764359da36f88aded3610 upstream.

If the machine is booted without any cpu_idle driver set
(b/c disable_cpuidle() has been called) we should follow
other users of cpu_idle API and check the return value
for NULL before using it.

Reported-and-tested-by: Mark van Dijk <mark@internecto.net>
Suggested-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Konrad Rzeszutek Wilk 2012-08-16 22:06:55 +02:00 committed by Greg Kroah-Hartman
parent 23a5a7a2da
commit 6535fb1535
1 changed files with 2 additions and 1 deletions

View File

@ -594,8 +594,9 @@ static int __init intel_idle_init(void)
intel_idle_cpuidle_driver_init();
retval = cpuidle_register_driver(&intel_idle_driver);
if (retval) {
struct cpuidle_driver *drv = cpuidle_get_driver();
printk(KERN_DEBUG PREFIX "intel_idle yielding to %s",
cpuidle_get_driver()->name);
drv ? drv->name : "none");
return retval;
}