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Date: Wed, 24 Mar 2010 16:27:10 +0530
From: Amit Shah <amit.shah@redhat.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 4/7] hvc_console: Fix race between hvc_close and hvc_remove
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On (Wed) Mar 24 2010 [21:45:44], Benjamin Herrenschmidt wrote:
> On Sun, 2010-03-21 at 08:04 +1100, Benjamin Herrenschmidt wrote:
> > On Fri, 2010-03-19 at 08:18 -0700, Greg Kroah-Hartman wrote:
> > > From: Amit Shah <amit.shah@redhat.com>
> > > 
> > > Alan pointed out a race in the code where hvc_remove is invoked. The
> > > recent virtio_console work is the first user of hvc_remove().
> > 
> > This causes hangs during boot on pseries machines. Haven't had a chance
> > to track that down yet, but please revert
> > e74d098c66543d0731de62eb747ccd5b636a6f4c for now.
> 
> Linus, any chance you can revert that one for now until we figure out
> what's wrong ?

Ben, can you confirm if the lockup you see is also due to the
task_is_waking() issue I found in a kvm guest?

That'll help me debug the issue.

Thanks.

		Amit