Re: 2.6.28-rc2-mm1: possible circular locking

From: Arjan van de Ven
Date: Wed Oct 29 2008 - 17:54:35 EST


On Wed, 29 Oct 2008 13:58:40 -0700
Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:

> We've been calling schedule_on_each_cpu() from within
> lru_add_drain_all() for ages. What changed to cause all this
> to start happening?

what started to get these out of the weed is that copy_*_user() is now
annotated to (potentially) take the mmap sem (which it does if there's
a fault)...
previously you had to actually fault to get the lock dependency noticed.

--
Arjan van de Ven Intel Open Source Technology Centre
For development, discussion and tips for power savings,
visit atty://www.lesswatts.org
--
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/