This patch (as1445) fixes a bug in the runtime PM core left over from
the addition of the no_callbacks flag. If this flag is set then it is
possible for rpm_suspend() to be called in_interrupt, so when
releasing spinlocks it's important not to re-enable interrupts.
To avoid an unnecessary save-and-restore of the interrupt flag, the
patch also inlines a pm_request_idle() call.
This fixes Bugzilla #27482.
(The offending code was added in 2.6.37, so it's not necessary to apply
this to any earlier stable kernels.)
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Reported-by: tim blechmann <tim@xxxxxxxxxx>
CC: <stable@xxxxxxxxxx>
---
Index: usb-2.6/drivers/base/power/runtime.c
===================================================================
--- usb-2.6.orig/drivers/base/power/runtime.c
+++ usb-2.6/drivers/base/power/runtime.c
@@ -407,12 +407,15 @@ static int rpm_suspend(struct device *de
goto out;
}
+ /* Maybe the parent is now able to suspend. */
if (parent && !parent->power.ignore_children && !dev->power.irq_safe) {
- spin_unlock_irq(&dev->power.lock);
+ spin_unlock(&dev->power.lock);
- pm_request_idle(parent);
+ spin_lock(&parent->power.lock);
+ rpm_idle(parent, RPM_ASYNC);
+ spin_unlock(&parent->power.lock);
- spin_lock_irq(&dev->power.lock);
+ spin_lock(&dev->power.lock);
}
out:
_______________________________________________
linux-pm mailing list
linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linux-foundation.org/mailman/listinfo/linux-pm
