Re: [PATCH 7/7] s390/vdso: Wire up getrandom() vdso implementation

Jason A. Donenfeld
2024-09-13T19:23:26Z

On Fri, Sep 13, 2024 at 07:32:06PM +0200, Heiko Carstens wrote:
> On Fri, Sep 13, 2024 at 05:22:09PM +0200, Jason A. Donenfeld wrote:
> > On Fri, Sep 13, 2024 at 05:13:28PM +0200, Jason A. Donenfeld wrote:
> > > On Fri, Sep 13, 2024 at 03:05:43PM +0200, Heiko Carstens wrote:
> > > > The vdso testcases vdso_test_getrandom and vdso_test_chacha pass.
> > >
> > > I'm trying to cross compile this but I'm getting:
> > >
> > > CC vdso_test_chacha
> > > /home/zx2c4/Projects/random-linux/tools/testing/selftests/../../../tools/arch/s390/vdso/vgetrandom-chacha.S: Assembler messages:
> > > /home/zx2c4/Projects/random-linux/tools/testing/selftests/../../../tools/arch/s390/vdso/vgetrandom-chacha.S:147: Error: Unrecognized opcode: `alsih'
> > >
> > > Any idea what's up?
> >
> > Looks like I needed `-march=arch9`. I can potentially rebuild my
> > toolchains to do this by default, though, if that's a normal thing to
> > have and this is just my toolchain being crappy. Or, if it's not a
> > normal thing to have, do we need to add it to the selftests Makefile?
>
> That needs to be fixed differently, since the kernel build would also
> fail when building for z10. Could you squash the below fix into this
> patch, please?

Done.

> So for the kernel itself including the vdso code, everything is
> correct now. But similar checks are missing within vdso_test_chacha.c.
> I'll provide something for that, so that the test case will be skipped
> if the required instructions are missing, but not today.

Okay. I would assume no rush there, because it's unlikely there are
those machines part of kselftest fleets anyway?

Jason