From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [REPORT] net: e1000e: possible data races
Date: Wed, 3 Oct 2018 21:18:41 +0800
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Cc: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
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To: jeffrey.t.kirsher@intel.com, davem@davemloft.net
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CPU0:
e1000e_get_stats64
     line 5944: spin_lock()
     e1000e_update_stats
         line 4949: hw->mac.tx_packet_delta = er32(TPT); [WRITE]

CPU1:
e1000_watchdog_task
     e1000e_update_adaptive
         line 1762: mac->tx_packet_delta [READ]
         line 1763: mac->tx_packet_delta [READ]
         line 1776: mac->tx_packet_delta [READ]

As for mac->tx_packet_delta, the WRITE operation in CPU0 is 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