Messages in this thread | | | Date | Fri, 11 Jan 2002 11:57:17 +0000 | From | Russell King <> | Subject | Re: [patch] O(1) scheduler, -H5 |
| |
On Fri, Jan 11, 2002 at 12:42:14PM +0100, Andi Kleen wrote: > When they hold the kernel lock in addition to the global cli() before > schedule() it should be ok. Only the behaviour of code not holding > kernel lock but global cli and calling schedule() has changed.
Agreed, however, there is one thing that has bugged me for a long time (and which I believe is causing someone a problem at the moment) - when we shut down a port, we're holding the BKL, and have global IRQs disabled. We unhook the port from the serial drivers chain, and maybe free and reclaim the IRQ with a different handler, and then disable the IRQ from the port in question.
If we happen to schedule within request_irq, it doesn't take too much imagination to see that Bad Things can happen.
(There is a report of complete lockup, and re-ordering stuff around here fixes the problem, but the example patch changed a number of things, and I'm trying to work towards a proper solution).
-- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |