Hi Christophe, On Fri, Nov 18, 2022 at 07:34:26PM +0000, Christophe Leroy wrote: > > +static __always_inline ssize_t > > +__cvdso_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state) > > +{ > > + struct vgetrandom_state *state = opaque_state; > > + const struct vdso_rng_data *rng_info = __arch_get_vdso_rng_data(); > > In order to ease wiring up to powerpc, can it be done the same way as > commit e876f0b69dc9 ("lib/vdso: Allow architectures to provide the vdso > data pointer") It is already. At least I think it is, unless I'm missing a subtle distinction? The call to __arch_get_vdso_rng_data() goes to arch-specific code, implemented in the 3/3 of this patch set for x86 inside of arch/x86/include/asm/vdso/getrandom.h. On powerpc, you'd make a powerpc-specific __arch_get_vdso_rng_data() instead of arch/powerpc/include/asm/vdso/getrandom.h. Or maybe I'm not reading that commit right? The commit message says something about __arch_get_vdso_rng_data() being problematic because of clobbering a register, but then the same commit still seems to call __arch_get_vdso_rng_data()? Is this one of those things where what you'd prefer is that I define an inline function, __cvdso_get_vdso_rng_data(), that by default calls __arch_get_vdso_rng_data(), but can be overridden on powerpc to do some other type of magic? But __arch_get_vdso_rng_data() is already an overiddable inline, so what would the difference be? Sorry if I'm a bit slow here to grok what's up. Jason