On Fri, Jan 18, 2008 at 03:48:02PM +0800, Dave Young wrote:
quoted text
> On Jan 18, 2008 3:38 PM, Jarek Poplawski <jarkao2@gmail.com> wrote:
...
quoted text
> > IMHO, it would be nice to get the real state of current lockdep
> > problems here to figure out if there is any chance to do this right &
> > without any warnings with current lockdep. If I got it right from
> > earlier threads it might be impossible with USB, at least.
> 
> I don't think so, usb doesn't be affected by struct class mutex, they
> only use the lock of struct device. As I replied before, the lockdep
> issue exist only between class_interface and class_device.

OK, but I've meant possibility of changing their own semaphores later.

quoted text
> > So, since I think these nesting levels seem to be wrong in 7/7 patch,
> > maybe it's better to exclude it from this patchset, and to try this as
> > testing for some time.
> 
> I may file the updated patch with more nesting changes and test it of
> course. Actually I should have done it, thanks.
...
quoted text
> 1) Using CLASS_NORMAL/CLASS_PARENT/CLASS_CHILD will be enough.
> or
> 2) Simply add SINGLE_LEVEL_NESTING in class_device_add and other
> class_device functions because it is the only possible nest-lock place
> as I know.

If SINGLE_LEVEL_NESTING is enough? (means 2 levels total)

I think you should more care about real (logical) relations here, than
what's enough to get rid of lockdep warnings.

Since there are not so much of these changes, you can try both
variants. I'll be glad to look at this - maybe I'll mangage to figure
out BTW, what it's all about...

Jarek P.
--
unsubscribe notice
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/