From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-26] cxgb4vf: fix mailbox data/control coherency
 domain race
Date: Mon, 10 Jan 2011 13:56:38 -0800 (PST)
Message-ID: <20110110.135638.267960720.davem@davemloft.net>
References: <1294696261-21209-1-git-send-email-leedom@chelsio.com>
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From: Casey Leedom <leedom@chelsio.com>
Date: Mon, 10 Jan 2011 13:51:01 -0800

> For the VFs, the Mailbox Data "registers" are actually backed by
> T4's "MA" interface rather than PL Registers (as is the case for
> the PFs).  Because these are in different coherency domains, the
> write to the VF's PL-register-backed Mailbox Control can race in
> front of the writes to the MA-backed VF Mailbox Data "registers".
> So we need to do a read-back on at least one byte of the VF Mailbox
> Data registers before doing the write to the VF Mailbox Control
> register.
> 
> Signed-off-by: Casey Leedom <leedom@chelsio.com>

Applied, thanks.