[PATCH v4 2/2] arm64: Introduce HWCAPS2_EXECONLY

[Catalin Marinas]

On Thu, Mar 25, 2021 at 07:00:00PM +0000, Will Deacon wrote:
> On Fri, Mar 12, 2021 at 05:38:11PM +0000, Vladimir Murzin wrote:
> > With EPAN supported it might be handy to user know that PROT_EXEC
> > gives execute-only permission, so advertise it via HWCAPS2_EXECONLY
> > 
> > Cc: Kees Cook <keescook at chromium.org>
> > Cc: Catalin Marinas <catalin.marinas at arm.com>
> > Signed-off-by: Vladimir Murzin <vladimir.murzin at arm.com>
> > ---
> >  arch/arm64/include/asm/hwcap.h      | 1 +
> >  arch/arm64/include/asm/sysreg.h     | 1 +
> >  arch/arm64/include/uapi/asm/hwcap.h | 1 +
> >  arch/arm64/kernel/cpufeature.c      | 3 +++
> >  arch/arm64/kernel/cpuinfo.c         | 1 +
> >  5 files changed, 7 insertions(+)
> 
> I still don't see the need for this patch. Can we avoid merging it until
> somebody has a use for it, please?

It's more about telling user-space that the feature is present though we
didn't do this last time we had exec-only permissions either. I was
hoping we can do better this time. OTOH, probably no-one will check for
this HWCAP anyway, so let's wait until someone asks for it.

-- 
Catalin