Re : [HW_RNG] How to use generic rng in kernel space

[moreau francis]

Michael Buesch wrote:
> So, if you have a special hwrng on your embedded board and you
> have some special driver in that board, why not interface
> directly from the driver to the hwrng-driver?

This is what I'm currently doing. I was just thinking to use the
new HW-RNG layer and drop common code...

> This is all pretty special case.
> In the hwrng-driver you could still additionally do a
> hrwng_register() to export the functionality to
> userspace, though.
> 

yes I would like to do that but there is a problem: I have no 
access to "rng_mutex" to synchronise hw accesses and I'm
wondering if there's any issue to use a mutex in driver init
code.

> 
> I am not a friend of a direct in-kernel hwrng access interface,
> because it may return crap data by definition. Many (all current)
> RNG devices may fail and return non-random data. If that's happily
> used by some in-kernel user by the interface, we are screwed.
> 
> Why can't you build your random-data consumer as module and load
> it later, when random data is available (and was carefully checked
> by various tests in rngd)?
> 

simply because in this embedded system, there's no module support.

thanks

Francis
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