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Subject: Re: Regression in RCU subsystem in latest mainline kernel
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <michael@ellerman.id.au>
Date: Tue, 25 Jun 2013 17:36:25 +1000
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Cc: Rojhalat Ibrahim <imr@rtschenk.de>,
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On Tue, 2013-06-25 at 17:19 +1000, Michael Ellerman wrote:
> Here's another trace from 3.10-rc7 plus a few local patches.
> 
> We suspect that the perf enable could be causing a flood of
> interrupts, but why
> that's clogging things up so badly who knows.

Additionally, perf being potentially NMIs , we might be hitting a bad
case of reentrance in RCU ... hard to tell.

Cheers,
Ben.