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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id b9sm5429988pfp.12.2020.05.07.10.52.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 May 2020 10:52:23 -0700 (PDT) Date: Thu, 7 May 2020 10:52:22 -0700 From: Kees Cook To: Luis Chamberlain Cc: cl@linux.com, akpm@linux-foundation.org, arnd@arndb.de, willy@infradead.org, aquini@redhat.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm: expand documentation over __read_mostly Message-ID: <202005071052.1522C624@keescook> References: <20200507161424.2584-1-mcgrof@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200507161424.2584-1-mcgrof@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 07, 2020 at 04:14:24PM +0000, Luis Chamberlain wrote: > __read_mostly can easily be misused by folks, its not meant for > just read-only data. There are performance reasons for using it, but > we also don't provide any guidance about its use. Provide a bit more > guidance over its use. > > Acked-by: Christoph Lameter > Signed-off-by: Luis Chamberlain Reviewed-by: Kees Cook -- Kees Cook