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Date:   Wed, 05 Sep 2018 08:10:02 -0700 (PDT)
Message-Id: <20180905.081002.193347914551729211.davem@davemloft.net>
To:     stefan.wahren@i2se.com
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V3] net: qca_spi: Fix race condition in spi transfers
From:   David Miller <davem@davemloft.net>
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From: Stefan Wahren <stefan.wahren@i2se.com>
Date: Wed,  5 Sep 2018 15:23:18 +0200

> With performance optimization the spi transfer and messages of basic
> register operations like qcaspi_read_register moved into the private
> driver structure. But they weren't protected against mutual access
> (e.g. between driver kthread and ethtool). So dumping the QCA7000
> registers via ethtool during network traffic could make spi_sync
> hang forever, because the completion in spi_message is overwritten.
> 
> So revert the optimization completely.
> 
> Fixes: 291ab06ecf676 ("net: qualcomm: new Ethernet over SPI driver for QCA700")
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>

Applied and queued up for -stable, thanks.