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From:   Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [REPORT] net: e100: possible data races
To:     jeffrey.t.kirsher@intel.com, davem@davemloft.net
Cc:     intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Message-ID: <8b3eba57-bdf3-3c0d-1889-12a971f277d1@gmail.com>
Date:   Wed, 3 Oct 2018 21:03:38 +0800
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CPU0:
e100_set_multicast_list
   e100_exec_cb
     line 854: spin_lock_irqsave()
     line 866: e100_configure (function pointer)
       line 1114: nic->flags [READ]
       line 1123: nic->flags [READ]

CPU1:
e100_watchdog
   line 1731: nic->flags [WRITE]
   line 1733: nic->flags [WRITE]

As for nic->flags, the WRITE operations in CPU0 are performed
with holding a spinlock, but the READ operations in CPU1 are performed
without holding this spinlock, so there may exist data races.

These possible races are detected by a runtime testing.
I do not find a good way to fix these races, so I only report them.


Best wishes,
Jia-Ju Bai