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Date: Wed, 21 Oct 2015 18:14:16 +0200
From: Andrew Lunn <andrew@lunn.ch>
To: Neil Armstrong <narmstrong@baylibre.com>
Cc: "David S. Miller" <davem@davemloft.net>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Guenter Roeck <linux@roeck-us.net>,
        vivien.didelot@savoirfairelinux.com, Fabian Frederick <fabf@skynet.be>,
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        linux-kernel@vger.kernel.org, nbd@openwrt.org,
        sergei.shtylyov@cogentembedded.com
Subject: Re: [PATCH] net: dsa: mv88e6060: Fix false positive lockdep splat
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On Wed, Oct 21, 2015 at 05:37:45PM +0200, Neil Armstrong wrote:
> Like the change made for mv88e6xxx, use mutex_lock_nested() to avoid
> lockdep to give false positives because of nested MDIO busses.

Hi Neil

We now have three instances of this, since mdio-mux.c has the same
code. Maybe now would be a good time to refactor this code into
mdiobus_read_nested() and mdiobus_write_nested() in mdio_bus.c?  At
the same time, add BUG_ON(in_interrupt()) similar to the non-nested
versions?

	Andrew