On Sat, Aug 04, 2012 at 11:56:35PM +0200, Rafael J. Wysocki wrote: > On Thursday, August 02, 2012, Konrad Rzeszutek Wilk wrote: > > 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-by: Mark van Dijk <m...@internecto.net> > > Tested-by: Mark van Dijk <m...@internecto.net> > > Suggested-by: Jan Beulich <jbeul...@suse.com> > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> > > --- > > drivers/idle/intel_idle.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c > > index f559088..7383aa0 100644 > > --- a/drivers/idle/intel_idle.c > > +++ b/drivers/idle/intel_idle.c > > @@ -607,7 +607,7 @@ static int __init intel_idle_init(void) > > retval = cpuidle_register_driver(&intel_idle_driver); > > if (retval) { > > What about: > > struct cpuidle_driver *drv = cpuidle_get_driver(); > > printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", > drv ? drv->name : "none"); > > > printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", > > - cpuidle_get_driver()->name); > > + cpuidle_get_driver() ? cpuidle_get_driver()->name : > > "none"); > > return retval; > > } > > > > > > Rafael
Here it is: >From a8b7aa06cacb5f42a90a0d4a0a1a95e230d43fc6 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> Date: Thu, 2 Aug 2012 10:31:52 -0400 Subject: [PATCH] intel_idle: Check cpu_idle_get_driver() for NULL before dereferencing it. 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-by: Mark van Dijk <m...@internecto.net> Tested-by: Mark van Dijk <m...@internecto.net> Suggested-by: Jan Beulich <jbeul...@suse.com> [v1: Redo per Rafael's suggestion] Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> --- drivers/idle/intel_idle.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index d0f59c3..6b313af 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -556,8 +556,9 @@ 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; } -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/