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([2620:15c:2c1:200:55c7:81e6:c7d8:94b]) by smtp.gmail.com with ESMTPSA id t24sm4921430pfh.21.2019.02.05.12.23.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 05 Feb 2019 12:23:19 -0800 (PST) Subject: Re: [PATCH v2 2/2] r8169: Avoid pointer aliasing To: Joe Perches , David Miller , thierry.reding@gmail.com Cc: hkallweit1@gmail.com, andrew@lunn.ch, nic_swsd@realtek.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20190204164213.30727-1-thierry.reding@gmail.com> <20190204164213.30727-2-thierry.reding@gmail.com> <20190204.192040.1074738183781998611.davem@davemloft.net> <8553086eaec167846992f1cff12aa388cee81767.camel@perches.com> <4aea523a3bc5be0d944f7ed9fadac276b7115002.camel@perches.com> From: Eric Dumazet Message-ID: Date: Tue, 5 Feb 2019 12:23:18 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <4aea523a3bc5be0d944f7ed9fadac276b7115002.camel@perches.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/05/2019 12:18 PM, Joe Perches wrote: > I still think adding __align() is unnecessary here unless > it follows something like a bool or a u8. This would be some historical side effect, and we do not want to rely on that. A security feature could in fact ask a compiler to perform random shuffling of automatic variables. ( a la __randomize_layout )