Re: [PATCH 2/5] gcc-plugins/stackleak: Use asm instrumentation to avoid useless register saving
From: Kees Cook
Date: Wed Jun 10 2020 - 16:03:32 EST
On Wed, Jun 10, 2020 at 06:47:14PM +0300, Alexander Popov wrote:
> On 09.06.2020 21:46, Kees Cook wrote:
> The inline asm statement that is used for instrumentation is arch-specific.
> Trying to add
> asm volatile("call stackleak_track_stack")
> in gcc plugin on aarch64 makes gcc break spectacularly.
Ah! Thank you, that eluded my eyes. :)
> I pass the target arch name to the plugin and check it explicitly to avoid that.
>
> Moreover, I'm going to create a gcc enhancement request for supporting
> no_caller_saved_registers attribute on aarch64.
For arm64 right now it looks like the plugin will just remain
"inefficient" in these cleanup, as before, yes?
--
Kees Cook