Re: [PATCH v10 4/4] x86: vdso: Wire up getrandom() vDSO implementation

From: Jason A. Donenfeld
Date: Tue Nov 29 2022 - 20:11:47 EST


Hi Thomas,

On Tue, Nov 29, 2022 at 11:52:05PM +0100, Thomas Gleixner wrote:
> On Tue, Nov 29 2022 at 22:06, Jason A. Donenfeld wrote:
> > Hook up the generic vDSO implementation to the x86 vDSO data page. Since
> > the existing vDSO infrastructure is heavily based on the timekeeping
> > functionality, which works over arrays of bases, a new macro is
> > introduced for vvars that are not arrays.
> >
> > The vDSO function requires a ChaCha20 implementation that does not write
> > to the stack, yet can still do an entire ChaCha20 permutation, so
> > provide this using SSE2, since this is userland code that must work on
> > all x86-64 processors.
>
> Way more consumable and looks about right.

Good.

> Please take your time and
> give others a chance to look at this lot before rushing out v11.

That's my plan indeed. Now that the patch is reviewable, I'll let it sit
for a while. In between v10 and v11, my scratch work will be in
<https://git.zx2c4.com/linux-rng/log/?h=vdso>, which is rebased often.

Thanks again for looking this over.

Jason