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Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu Subject: Re: [PATCH v14 1/7] x86/cet/ibt: Add Kconfig option for user-mode Indirect Branch Tracking Message-ID: <20201012191511.GC14048@grain> References: <20201012154530.28382-1-yu-cheng.yu@intel.com> <20201012154530.28382-2-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201012154530.28382-2-yu-cheng.yu@intel.com> User-Agent: Mutt/1.14.6 (2020-07-11) Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Mon, Oct 12, 2020 at 08:45:24AM -0700, Yu-cheng Yu wrote: ... > + the application support it. When this feature is enabled, > + legacy non-IBT applications continue to work, but without > + IBT protection. > + Support for this feature is only known to be present on > + processors released in 2020 or later. CET features are also > + known to increase kernel text size by 3.7 KB. It seems the last sentence is redundant - new features always bloat the kernel code and precise size may differ depending on compiler and options. Surely this can be patched on top.