Date: Thu, 18 May 2006 09:58:10 +0200
From: Ingo Molnar <mingo@elte.hu>
To: john stultz <johnstul@us.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Thomas Gleixner <tglx@linutronix.de>,
       mingo@redhat.com, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [RFC][-rt PATCH] Try to safely error out when mixing pi/non-pi futex operations on the same futex.
Message-ID: <20060518075810.GB30387@elte.hu>
References: <1147900129.9363.7.camel@localhost.localdomain>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1147900129.9363.7.camel@localhost.localdomain>
User-Agent: Mutt/1.4.2.1i
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 931
Lines: 26


* john stultz <johnstul@us.ibm.com> wrote:

> Ingo,
> 	We've been seeing some oopses because there are waiters on pi 
> futexes that do not have pi_states. This seems to be because they were 
> used w/ futex_wait in one path and futex_lock_pi in another.

indeed, that's a bug.

> I'm told this shouldn't ever happen, but if it did, the kernel should 
> safely error out, instead of oopsing or never releasing a lock.
> 
> Not sure if this is a solid fix (it does build and boot), but 
> hopefully it will stir up some discussion.

applied. I made some small fixes: i made the printk rate-limited and 
dependent on CONFIG_DEBUG_RT_MUTEXES. The right thing is indeed to 
-EINVAL.

	Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/