Messages in this thread | | | Date | Sat, 30 Mar 2002 11:06:25 -0800 | From | Andrew Morton <> | Subject | Re: [patch] block/IDE/interrupt lockup |
| |
Alan Cox wrote: > > > The kernel calls request_irq() inside cli() in lots of places. > > That's the same bug: "if you called cli(), how come you're > > allowing kmalloc to clear it?". > > Those places should if possible be fixed. I take patches. If we can get 2.4 > to BUG() on those kmalloc violations and clean them up it sounds like > progress
What I'd like is a debugging function `can_sleep()'. This is good for documentary purposes, and will catch bugs.
So kmalloc() would gain:
if (gfp_flags & __GFP_WAIT) can_sleep();
can_sleep() would do the following:
- If CONFIG_PREEMPT, check the locking depth (minus BKL depth), whine if non-zero.
- If inside cli(), whine.
- If inside __cli(), also whine (not really a bug, but a design error).
- whining will include generation of a backtrace.
I suspect a 2.4 version would generate too many bug reports :) It would have to implement its own lock depth accounting if we want the sleep-inside-spinlock checking.
There's some arch-dependent stuff in there. I'll do a 2.5 patch. I suspect it'll generate showers of stuff. We can feed fixes back into 2.4.
- - 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/
| |