From mboxrd@z Thu Jan  1 00:00:00 1970
From: Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: [NET]: Fix possible dev_deactivate race condition
Date: Fri, 19 Oct 2007 17:29:21 +0800
Message-ID: <20071019092921.GA12380@gondor.apana.org.au>
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Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>, linuxppc-dev@ozlabs.org,
	Thomas Gleixner <tglx@linutronix.de>, netdev@vger.kernel.org,
	akpm@linux-foundation.org, Linus Torvalds <torvalds@linux-foundation.org>,
	Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
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On Fri, Oct 19, 2007 at 09:35:19AM +0200, Peter Zijlstra wrote:
>
> >         /* Wait for outstanding qdisc_run calls. */
> > -       while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
> > -               yield();
> > +       do {
> > +               while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
> > +                       yield();
> > +
> 
> Ouch!, is there really no sane locking alternative? Hashed waitqueues
> like for the page lock come to mind.

Well if we ever moved the transmission to full process context
then we'll gladly accept your patch :)

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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