Re: Linux 3.19-rc5

[Rafael J. Wysocki]

On Thursday, January 29, 2015 05:25:07 PM Linus Torvalds wrote:
> On Thu, Jan 29, 2015 at 5:12 PM, Linus Torvalds
> <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > The WARN() was already changed to a WARN_ONCE().
> 
> Oh, but I notice that the "__set_current_state(TASK_RUNNING) ends up
> always happening.
> 
> So I think the right fix is to:
> 
>  - warn once like we do
> 
>  - but *not* do that __set_current_state() which was always total crap anyway
> 
> Why do I say "total crap"? Because of two independent issues:
> 
>  (a) it actually changes behavior for a debug vs non-debug kernel,
> which is a really bad idea to begin with
> 
>  (b) it's really wrong. The whole "nested sleep" case was never a
> major bug to begin with, just a possible inefficiency where constant
> nested sleeps would possibly make the outer sleep not sleep. But that
> "could possibly make" case was the unlikely case, and the debug patch
> made it happen *all* the time by explicitly setting things running.
> 
> So I think the proper patch is the attached.

I applied the patch and compiled the kernel with CONFIG_DEBUG_ATOMIC_SLEEP
set again.  The warning is back, so the DEBUG_ATOMIC_SLEEP thing appears to
be working (and I don't really care about the freaking warning anyway), but the
pccardd load issue is gone, so the patch fixes the problem for me.  Thanks!

Rafael

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/