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Date:   Sat, 13 Apr 2019 20:24:39 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Igor Russkikh <Igor.Russkikh@aquantia.com>
Cc:     "David S . Miller" <davem@davemloft.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        Nikita Danilov <Nikita.Danilov@aquantia.com>,
        Dmitry Bogdanov <Dmitry.Bogdanov@aquantia.com>
Subject: Re: [PATCH netnext 12/16] net: aquantia: wrap fw ops by mutex
Message-ID: <20190413182439.GS17901@lunn.ch>
References: <cover.1555158087.git.igor.russkikh@aquantia.com>
 <4c9a8c7d1771b61627beb917bd0da64d5f485aa5.1555158087.git.igor.russkikh@aquantia.com>
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On Sat, Apr 13, 2019 at 12:32:11PM +0000, Igor Russkikh wrote:
> From: Nikita Danilov <ndanilov@aquantia.com>
> 
> Since fw ops may be invoked from different threads all its invocation
> must be wrapped by mutex.

Do all fw ops go through hw_atl_utils_fw_rpc_wait()?

My experience with the mv88e6xxx driver is that you forget a lock
somewhere. So we added code in the low level register access to check
the lock has been taken:

        if (unlikely(!mutex_is_locked(&chip->reg_lock))) {
                dev_err(chip->dev, "Switch registers lock not held!\n");
                dump_stack();
        }

	Andrew