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Peter Anvin" , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] x86/boot: avoid recompiling kaslr.c for incremental rebuilds Message-ID: <202402201133.3FC7CE9@keescook> References: <20240220192144.2050167-1-jannh@google.com> <20240220192144.2050167-4-jannh@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240220192144.2050167-4-jannh@google.com> On Tue, Feb 20, 2024 at 08:21:44PM +0100, Jann Horn wrote: > Currently, every kernel rebuild needs to compile kaslr.c again because > UTS_VERSION changes on every rebuild. > Move the build string into a separate object file to speed things up. Heh, I think I don't see this because I force my UTS_VERSION to stay still by default so I can do binary difference comparisons more easily. :P args += ['KBUILD_BUILD_TIMESTAMP=1970-01-01'] args += ['KBUILD_BUILD_VERSION=1'] args += ['KBUILD_BUILD_USER=user'] args += ['KBUILD_BUILD_HOST=host'] -- Kees Cook