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Miller" , Andreas Larsson , linux-snps-arc@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-openrisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, Michal =?iso-8859-1?Q?Such=E1nek?= , Jonathan Corbet , linux-doc@vger.kernel.org Subject: Re: [patch 02/18] randomize_kstack: Provide add_random_kstack_offset_irqsoff() Message-ID: <202607090922.4ECAE32C07@keescook> References: <20260707181957.433213175@kernel.org> <20260707190253.768842729@kernel.org> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260707190253.768842729@kernel.org> On Tue, Jul 07, 2026 at 09:06:02PM +0200, Thomas Gleixner wrote: > add_random_kstack_offset() uses get/put_cpu_var() which is pointless > overhead when it is invoked from low level entry code with interrupts > disabled. > > Provide a irqsoff() variant, which avoids that. > > Signed-off-by: Thomas Gleixner Seems good. I don't think macro'izing the interior is worth it since both cases are very short, with only the lockdep and raw bits changed. Reviewed-by: Kees Cook -Kees -- Kees Cook