Re: [2.4.17/18pre] VM and swap - it's really unusable

Russell King
2002-01-13T11:40:15Z

On Sat, Jan 12, 2002 at 10:10:55PM -0500, Robert Love wrote:
> It can if we increment the preempt_count in disable_irq_nosync and
> decrement it on enable_irq.

Who says you're going to be enabling IRQs any time soon? AFAIK, there is
nothing that requires enable_irq to be called after disable_irq_nosync.

In fact, you could well have the following in a driver:

/* initial shutdown of device */

disable_irq_nosync(i); /* or disable_irq(i); */

/* other shutdown stuff */

free_irq(i, private);

and you would have to audit all drivers to find out if they did this -
this would seriously damage your preempt_count.

--
Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux