From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Lunn <andrew@lunn.ch>
Subject: Re: [PATCH] net: dsa: mv88e6060: Fix false positive lockdep splat
Date: Wed, 21 Oct 2015 18:14:16 +0200
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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>,
	Pavel Nakonechny <pavel.nakonechny@skitlab.ru>,
	Joe Perches <joe@perches.com>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org, nbd@openwrt.org,
	sergei.shtylyov@cogentembedded.com
To: Neil Armstrong <narmstrong@baylibre.com>
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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