[linux-pm] [RFC][PATCH 2/2] PM: Rework handling of interrupts during suspend-resume

[Linus Torvalds]

On Wed, 25 Feb 2009, Alan Stern wrote:

> On Tue, 24 Feb 2009, Rafael J. Wysocki wrote:
> 
> > I think the most important source of level triggered interrupts are PCI
> > devices, so perhaps we can make the PCI PM core use bit 10 of the PCI Device
> > Control register to prevent devices from generating INTx after the drivers'
> > suspend routines have been executed?
> 
> I wish that were true.  As I recall, the original PCI specification did
> not define this bit, and older PCI devices don't support it.  So you
> can't count on being able to supress interrupt generation this way.  

It's definitely a new feature. In fact, I think even the current one makes 
it optional, so even for "new" devices it's very unclear how many of them 
actually support that bit.

			Linus