[PATCH v2 1/2] hwrng: fetch randomness only after device init

Amit Shah
2014-07-09T13:25:24Z

On (Wed) 09 Jul 2014 [09:17:37], Jason Cooper wrote:
> On Wed, Jul 09, 2014 at 06:38:22PM +0530, Amit Shah wrote:
> > On (Wed) 09 Jul 2014 [07:53:17], Jason Cooper wrote:
> > > On Sat, Jul 05, 2014 at 11:04:52AM +0530, Amit Shah wrote:
> > > > Commit d9e7972619334 "hwrng: add randomness to system
from rng sources"
> > > > added a call to rng_get_data() from the hwrng_register()
function.
> > > > However, some rng devices need initialization before data
can be read
> > > > from them.
> > > >
> > > > This commit makes the call to rng_get_data() depend on no
init fn
> > > > pointer being registered by the device.  If an init function
is
> > > > registered, this call is made after device init.
> > > >
> > > > CC: Kees Cook <keescook at chromium.org>
> > > > CC: Jason Cooper <jason at lakedaemon.net>
> > > > CC: Herbert Xu <herbert at gondor.apana.org.au>
> > > > CC: <stable at vger.kernel.org> # For v3.15+
> > > > Signed-off-by: Amit Shah <amit.shah at redhat.com>
> > > > ---
> > > >  drivers/char/hw_random/core.c | 31
+++++++++++++++++++++++++------
> > > >  1 file changed, 25 insertions(+), 6 deletions(-)
> > >
> > > Thanks for cleaning this up!
> >
> > Thanks!
> >
> > Any thoughts on the follow-up patch posted later that resolves some of
> > the weirdness in init?
>
> hmm, I'd rather see an init function for virtio-rng that checks the bit
> and returns 0 or -EAGAIN.  With your proposed change, you would get
> hangs again.

Confused; I meant the patch in

https://lkml.org/lkml/2014/7/7/58

		Amit