On Mon, Feb 29, 2016 at 08:35:41PM +0100, Thomas Gleixner wrote: > On Sat, 27 Feb 2016, Brian Gerst wrote: > > > arch_cpu_idle_prepare(); > > > cpu_idle_loop(); > > > } > > > > Does this actually work with stack protector enabled? > > boot_init_stack_canary() is inlined while arch_cpu_idle_prepare() is > > not. > > Stupid me. No it does of course not. I could have sworn that I tested that, > but obvioulsy not. > > I drop that patch, but actually the real question is whether we can drop that > '#ifdef x86' around that boot_init_stack_canary() invocation. > > AFAICT, neither arm, arm64 nor mips and sh call it on anything else than the > boot cpu. I can't see why that would be an issue on those architectures and > why it would be a problem if the boot cpu calls it again here. > > CC'ed the relevant maintainers. Is there any issue with the patch below?
On arm[64], the canary is unfortunately global, so I don't think it would be safe to update it live like this without effectively stopping the machine and forcing everybody into idle. Will
