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Kemerlis" , Juerg Haefliger , Tycho Andersen , Marco Benatto , David Woodhouse Subject: Re: [RFC PATCH v7 12/16] xpfo, mm: remove dependency on CONFIG_PAGE_EXTENSION References: Date: Wed, 16 Jan 2019 16:01:05 +0100 In-Reply-To: (Khalid Aziz's message of "Thu, 10 Jan 2019 14:09:44 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Khalid Aziz writes: > From: Julian Stecklina > > Instead of using the page extension debug feature, encode all > information, we need for XPFO in struct page. This allows to get rid of > some checks in the hot paths and there are also no pages anymore that > are allocated before XPFO is enabled. I have another patch lying around that turns the XPFO per-page locks into bit spinlocks and thus get the size of struct page to <= 64 byte again. In case someone's interested, ping me. Julian