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Mon, 04 May 2020 10:34:03 -0700 (PDT) Date: Mon, 4 May 2020 10:33:56 -0700 From: Sami Tolvanen To: Will Deacon Subject: Re: [PATCH v11 01/12] add support for Clang's Shadow Call Stack (SCS) Message-ID: <20200504173356.GA7200@google.com> References: <20200416161245.148813-1-samitolvanen@google.com> <20200416161245.148813-2-samitolvanen@google.com> <20200420171727.GB24386@willie-the-truck> <20200420211830.GA5081@google.com> <20200422173938.GA3069@willie-the-truck> <20200422235134.GA211149@google.com> <202004231121.A13FDA100@keescook> <20200424112113.GC21141@willie-the-truck> <20200427204546.GA80713@google.com> <20200504165227.GB1833@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200504165227.GB1833@willie-the-truck> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200504_103410_122182_5B61449F X-CRM114-Status: GOOD ( 13.73 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Juri Lelli , kernel-hardening@lists.openwall.com, Peter Zijlstra , Catalin Marinas , Marc Zyngier , Masahiro Yamada , clang-built-linux@googlegroups.com, Ingo Molnar , Laura Abbott , Dave Martin , Kees Cook , Jann Horn , Steven Rostedt , linux-arm-kernel@lists.infradead.org, Michal Marek , Ard Biesheuvel , Nick Desaulniers , linux-kernel@vger.kernel.org, Miguel Ojeda , James Morse , Masami Hiramatsu Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, May 04, 2020 at 05:52:28PM +0100, Will Deacon wrote: > On Mon, Apr 27, 2020 at 01:45:46PM -0700, Sami Tolvanen wrote: > > I agree that allocating from a kmem_cache isn't ideal for safety. It's a > > compromise to reduce memory overhead. > > Do you think it would be a problem if we always allocated a page for the > SCS? Yes, the memory overhead was deemed too large for Android devices, which have thousands of threads running. Sami _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel