Re: [PATCH 1/8] stop_machine: cpu_stopper_thread() must check done != NULL

From: Oleg Nesterov
Date: Tue Nov 17 2015 - 11:57:30 EST


On 11/16, Tejun Heo wrote:
>
> On Sun, Nov 15, 2015 at 08:33:11PM +0100, Oleg Nesterov wrote:
> > stop_one_cpu_nowait(fn) will crash the kernel if the callback returns
> > nonzero, work->done == NULL in this case.
> >
> > This needs more cleanups, cpu_stop_signal_done() is called right after
> > we check done != NULL and it does the same check.
> >
> > Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
>
> Acked-by: Tejun Heo <tj@xxxxxxxxxx>

Thanks!

> cc stable?

Yes, I was going to add -stable initially. And perhaps this makes sense
anyway, the patch is really trivial.

OTOH I have checked the history, none of cpu_stop_signal_done's callbacks
ever returned non-zero, so I decided to not spam -stable.

Oleg.

--
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/