From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Sasha Levin <levinsasha928@gmail.com>
Cc: "linux-kernel@vger.kernel.org List" <linux-kernel@vger.kernel.org>
Subject: Re: rcu: BUG on exit_group
Date: Thu, 3 May 2012 10:01:01 -0700 [thread overview]
Message-ID: <20120503170101.GF2592@linux.vnet.ibm.com> (raw)
In-Reply-To: <CA+1xoqepggR4YRzDXFz=Hk9EeXACMRyeXorQm7rE3r5MQyY6Fw@mail.gmail.com>
On Thu, May 03, 2012 at 05:55:14PM +0200, Sasha Levin wrote:
> On Thu, May 3, 2012 at 5:41 PM, Paul E. McKenney
> <paulmck@linux.vnet.ibm.com> wrote:
> > On Thu, May 03, 2012 at 10:57:19AM +0200, Sasha Levin wrote:
> >> Hi Paul,
> >>
> >> I've hit a BUG similar to the schedule_tail() one when. It happened
> >> when I've started fuzzing exit_group() syscalls, and all of the traces
> >> are starting with exit_group() (there's a flood of them).
> >>
> >> I've verified that it indeed BUGs due to the rcu preempt count.
> >
> > Hello, Sasha,
> >
> > Which version of -next are you using? I did some surgery on this
> > yesterday based on some bugs Hugh Dickins tracked down, so if you
> > are using something older, please move to the current -next.
>
> I'm using -next from today (3.4.0-rc5-next-20120503-sasha-00002-g09f55ae-dirty).
Hmmm... Looking at this more closely, it looks like there really is
an attempt to acquire a mutex within an RCU read-side critical section,
which is illegal. Could you please bisect this?
Thanx, Paul
next prev parent reply other threads:[~2012-05-03 17:01 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-03 8:57 rcu: BUG on exit_group Sasha Levin
2012-05-03 15:41 ` Paul E. McKenney
2012-05-03 15:55 ` Sasha Levin
2012-05-03 17:01 ` Paul E. McKenney [this message]
2012-05-04 4:08 ` Sasha Levin
2012-05-04 5:33 ` Paul E. McKenney
2012-05-09 4:59 ` KAMEZAWA Hiroyuki
2012-05-09 13:57 ` Paul E. McKenney
2012-05-09 20:36 ` Hugh Dickins
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