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Date: Tue, 22 May 2018 18:47:02 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Bo Chen <chenbo@pdx.edu>
Cc: jeffrey.t.kirsher@intel.com, davem@davemloft.net,
        intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] e1000: check the return of pci_get_drvdata() in
 e1000_remove()
Message-ID: <20180522184702.64cd62f6@xeon-e3>
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On Tue, 22 May 2018 17:17:43 -0700
Bo Chen <chenbo@pdx.edu> wrote:

> This check on pci_get_drvdata() prevents potential invalid pointer dereferences,
> and is a common practice in *_remove() functions from other drivers, such as
> 'intel/e100.c', 'amd/pcnet32.c', 'realtek/8139too.c', and 'broadcom/tg3.c'.
> 
> Signed-off-by: Bo Chen <chenbo@pdx.edu>

Why check for something that can never be true.
You are creating dead code paths that can never be exercised.