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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Subject: Re: [PATCH] Fix USB suspend/resume crasher
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> 
> Well, it's there (actually the problem occurs in vanilla 2.6.15-rc2-mm1 that
> contains the patch).  Do you mean it should go before the
> 
> if (readl(&ehci->regs->configured_flag) != FLAG_CF)
> 		goto restart;
> 
> thing?

Yes.

> > It may be worth following it with a memory barrier actually... just in case
> > (due to the absence of locks in that area).
> 
> wmb()?

Yup.

I wrote that patch against a tree that had different things in that
function, Greg merged it by hand but he got that little bit wrong
unfortunately. I'll send a new patch later today.

Ben.