Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752245AbaGJIpd (ORCPT ); Thu, 10 Jul 2014 04:45:33 -0400 Received: from helcar.apana.org.au ([209.40.204.226]:42831 "EHLO helcar.apana.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751985AbaGJIpa (ORCPT ); Thu, 10 Jul 2014 04:45:30 -0400 Date: Thu, 10 Jul 2014 16:45:14 +0800 From: Herbert Xu To: Jason Cooper Cc: Amit Shah , linux-kernel@vger.kernel.org, Virtualization List , Rusty Russell , keescook@chromium.org, stable@vger.kernel.org Subject: Re: [PATCH v2 2/2] virtio: rng: ensure reads happen after successful probe Message-ID: <20140710084514.GA15418@gondor.apana.org.au> References: <20140709161836.GQ13433@titan.lakedaemon.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140709161836.GQ13433@titan.lakedaemon.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 09, 2014 at 12:18:36PM -0400, Jason Cooper wrote: > On Sat, Jul 05, 2014 at 11:04:53AM +0530, Amit Shah wrote: > > The hwrng core asks for random data in the hwrng_register() call itself > > from commit d9e7972619. This doesn't play well with virtio -- the > > DRIVER_OK bit is only set by virtio core on a successful probe, and > > we're not yet out of our probe routine when this call is made. This > > causes the host to not acknowledge any requests we put in the virtqueue, > > and the insmod or kernel boot process just waits for data to arrive from > > the host, which never happens. > > > > CC: Kees Cook > > CC: Jason Cooper > > CC: Herbert Xu > > CC: # For v3.15+ > > Signed-off-by: Amit Shah > > --- > > drivers/char/hw_random/core.c | 6 ++++++ > > drivers/char/hw_random/virtio-rng.c | 10 ++++++++++ > > 2 files changed, 16 insertions(+) > > Yeah, I don't think there's any viable way to get random data out of > virtio-rng at probe time... :-( > > Reviewed-by: Jason Cooper OK, if there are no more objections I will take these two patches. Thanks! -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/