Re: [PATCH 2/3] sched: fix static keys race in sched_feat

From: Steven Rostedt
Date: Fri Jun 28 2013 - 23:03:33 EST


On Fri, 2013-06-28 at 22:30 +0000, jbaron@xxxxxxxxxx wrote:
> As pointed out by Andi Kleen, thue usage of static keys can be racy in

"thue"

> sched_feat_disable vs. sched_feat_enable(). Currently, we first check the
> value of keys->enabled, and subsequently update the branch direction. This,
> can be racy and can potentially leave the keys in an inconsistent state.
>
> Fix the race by using static_key_slow_set_true()/false(), which does the the
> check and set using the jump_label_mutex.
>
> Signed-off-by: Jason Baron <jbaron@xxxxxxxxxx>

-- Steve


--
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/