Re: [patch 02/18] randomize_kstack: Provide add_random_kstack_offset_irqsoff()
Kees Cook <[email protected]> Thu, 9 Jul 2026 09:23:47 -0700
| Newsgroups | org.kernel.vger.linux-alpha,dev.linux.lists.loongarch,org.infradead.lists.linux-riscv,org.infradead.lists.linux-snps-arc,org.infradead.lists.linux-um,org.kernel.vger.linux-arch,org.kernel.vger.linux-csky,org.kernel.vger.linux-doc,org.kernel.vger.linux-hexagon,org.kernel.vger.linux-kernel,org.kernel.vger.linux-m68k,org.kernel.vger.linux-mips,org.kernel.vger.linux-openrisc,org.kernel.vger.linux-parisc,org.kernel.vger.linux-s390,org.kernel.vger.linux-sh,org.kernel.vger.sparclinux,org.ozlabs.lists.linuxppc-dev |
|---|---|
| Message-ID | <202607090922.4ECAE32C07@keescook> |
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 <[email protected]> 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 <[email protected]> -Kees -- Kees Cook