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Message-ID: <1352866404.23412.17.camel@pasglop>
Subject: Re: HVC console breakage
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Anton Blanchard <anton@samba.org>
Date: Wed, 14 Nov 2012 15:13:24 +1100
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Cc: linuxppc-dev@lists.ozlabs.org, paulus@samba.org, gregkh@linuxfoundation.org,
 Paul Mackerras <paulus@au1.ibm.com>, jslaby@suse.cz, alan@linux.intel.com
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On Wed, 2012-11-14 at 13:57 +1100, Anton Blanchard wrote:
> Hi,
> 
> Commit bdb498c20040 (TTY: hvc_console, add tty install) breaks HVC on
> ppc64. It looks a bit like a refcounting issue and we end up releasing
> the tty. I haven't had a change to look closer yet.

Adding Paulus who is looking into it. So far what we observe is that
something (possibly a close() on a hvc tty by userspace) causes the port
to be destroyed permanently. Typically hits with fedora 17.

Cheers,
Ben.