From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [patch 2/3] s390: iucv - avoid deadlock between
 iucv_path_connect and tasklet
Date: Sat, 14 Jul 2007 19:03:50 -0700 (PDT)
Message-ID: <20070714.190350.95894917.davem@davemloft.net>
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	<20070713085245.495093000@linux.vnet.ibm.com>
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From: Ursula Braun <braunu@de.ibm.com>
Date: Fri, 13 Jul 2007 10:50:55 +0200

> From: Ursula Braun <braunu@de.ibm.com>
> 
> An iucv deadlock may occur, where one CPU is spinning on the
> iucv_table_lock for iucv_tasklet_fn(), while another CPU is holding
> the iucv_table_lock for an iucv_path_connect() and is waiting for
> the first CPU in an smp_call_function.
> Solution: replace spin_lock in iucv_tasklet_fn by spin_trylock and
> reschedule tasklet in case of non-granted lock.
> 
> Signed-off-by: Ursula Braun <braunu@de.ibm.com>
> Acked-by: Frank Pavlic <fpavlic@de.ibm.com>

Applied.