Re: [PATCH V3] net: qca_spi: Fix race condition in spi transfers

[David Miller]

From: Stefan Wahren <stefan.wahren@xxxxxxxx>
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@xxxxxxxx>

Applied and queued up for -stable, thanks.