Re: [PATCH v15 17/17] selftests, arm64: add a selftest for passing tagged pointers to kernel

Catalin Marinas
2019-05-31T16:22:17Z

On Fri, May 31, 2019 at 04:21:48PM +0200, Andrey Konovalov wrote:
> On Wed, May 22, 2019 at 4:16 PM Catalin Marinas <catalin.marinas@arm.com> wrote:
> > On Mon, May 06, 2019 at 06:31:03PM +0200, Andrey Konovalov wrote:
> > > This patch is a part of a series that extends arm64 kernel ABI to allow to
> > > pass tagged user pointers (with the top byte set to something else other
> > > than 0x00) as syscall arguments.
> > >
> > > This patch adds a simple test, that calls the uname syscall with a
> > > tagged user pointer as an argument. Without the kernel accepting tagged
> > > user pointers the test fails with EFAULT.
> >
> > That's probably sufficient for a simple example. Something we could add
> > to Documentation maybe is a small library that can be LD_PRELOAD'ed so
> > that you can run a lot more tests like LTP.
>
> Should I add this into this series, or should this go into Vincenzo's patchset?

If you can tweak the selftest Makefile to build a library and force it
with LD_PRELOAD, you can keep it with this patch. It would be easier to
extend to other syscall tests, signal handling etc.

--
Catalin