To: sergei.shtylyov@cogentembedded.com, davem@davemloft.net,
        niklas.soderlund+renesas@ragnatech.se, geert+renesas@glider.be,
        laurent.pinchart@ideasonboard.com, horms+renesas@verge.net.au
Cc: netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [BUG] renesas/sh_eth: two possible sleep-in-atomic bugs in
 sh_eth_set_link_ksettings and sh_eth_nway_reset
Message-ID: <45698118-3050-d1c5-4e48-c318d0cd164d@gmail.com>
Date: Wed, 13 Dec 2017 11:39:07 +0800
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Accoring to drivers/net/ethernet/renesas/sh_eth.c, the driver may sleep 
under a spinlock.
The function call paths are:
sh_eth_set_link_ksettings (acquire the spinlock)
   phy_ethtool_ksettings_set
     phy_start_aneg
       phy_start_aneg_priv
         mutex_lock --> may sleep

sh_eth_nway_reset (acquire the spinlock)
   phy_start_aneg
     phy_start_aneg_priv
       mutex_lock --> may sleep

I do not find a good way to fix them, so I only report.
These possible bugs are found by my static analysis tool (DSAC) and 
checked by my code review.


Thanks,
Jia-Ju Bai