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Date: Tue, 25 Jun 2013 11:50:57 +1000
From: Michael Ellerman <michael@ellerman.id.au>
To: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Subject: Re: [PATCH] Do not update sysfs cpu registration from invalid context
Message-ID: <20130625015057.GC14051@concordia>
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On Mon, Jun 24, 2013 at 09:14:23AM -0500, Nathan Fontenot wrote:
> The topology update code that updates the cpu node registration in sysfs
> should not be called while in stop_machine(). The register/unregister
> calls take a lock and may sleep.
> 
> This patch moves these calls outside of the call to stop_machine().

What happens? Do we lockup or do you just get a warning?

And what commit introduced the breakage?

cheers