Re: + futex-runtime-enable-pi-and-robust-functionality.patch addedto -mm tree

From: Josh Boyer
Date: Thu Mar 27 2008 - 08:04:20 EST


On Thu, 2008-03-27 at 14:48 +1100, Benjamin Herrenschmidt wrote:
> On Thu, 2008-03-27 at 14:32 +1100, Benjamin Herrenschmidt wrote:
> > > Hmm, not sure whether there is such code, but then it would be not too bad
> > > to add
> > >
> > > if (!p)
> > > return -EFAULT;
> > >
> > > to the S390 implementations which only read data and have an exception
> > > fixup.
> >
> > I have a different problem on some embedded powerpc's where the TLB miss
> > code isn't checking for the cached pgdir pointer being NULL (which
> > happens because we are early at boot and haven't activated an mm). So we
> > end up either taking recursive faults or going into lalaland walking
> > the page tables.
> >
> > It happens on some unreleased code, I'll verify if it happens on
> > 8xx/4xx/etc... in a minute, and will cook a patch if it does.
>
> Ok, so everything released seems to be fine. It will use swapper_pg_dir
> which on 32 bits will do the right thing. Pfiew ! So only some stuff I'm
> still working on breaks, I'll fix it.

I try to test at least the -rc releases on 4xx as they come out, if not
a daily git update, and this never bit on 4xx for the reasons you
stated. Glad we have similar results.

josh

--
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/