Re: a whole bunch of crashes since todays -mm merge.

From: Andrew Morton
Date: Thu Jun 07 2012 - 21:04:29 EST


On Thu, 7 Jun 2012 17:52:52 -0700 Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:

> On Thu, Jun 7, 2012 at 5:24 PM, Dave Jones <davej@xxxxxxxxxx> wrote:
> > I just started seeing crashes while doing simple things, like logging on a console..
>
> I'm looking at it right now, and the sync_mm_rss() patch is pure
> garbage. In many ways.
>
> You can't do sync_mm_rss() from mmdrop(), because there's no reason to
> believe that the task that does mmdrop() does it on its own active_mm.
> And even if you *could* do it there, it's still horribly wrong,
> because it does it at the end *after* it already freed the mm!
>
> Does it go away if you revert that (commit 40af1bbdca47). I wish I
> hadn't merged it, or that I had noticed how horrible it was before I
> pushed out.
>

It appears this is due to me fat-fingering conflict resolution last
week. That hunk is supposed to be in mm_release(), not mmput().

It's probably best to throw the patch away for now - we'll try again.
--
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/