Received-SPF: pass (google.com: best guess record for domain of linux-crypto-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 15 Nov 2019 23:32:29 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     "Sverdlin, Alexander (Nokia - DE/Ulm)" <alexander.sverdlin@nokia.com>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        Matt Mackall <mpm@selenic.com>,
        Vitaly Andrianov <vitalya@ti.com>
Subject: Re: [PATCH] hwrng: ks-sa: Add minimum sleep time before ready-polling
Message-ID: <20191116073229.GA161720@sol.localdomain>
References: <20191106093019.117233-1-alexander.sverdlin@nokia.com>
 <20191115060610.2sjw7stopxr73jhn@gondor.apana.org.au>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20191115060610.2sjw7stopxr73jhn@gondor.apana.org.au>
User-Agent: Mutt/1.12.2 (2019-09-21)
Sender: linux-crypto-owner@vger.kernel.org
Precedence: bulk

On Fri, Nov 15, 2019 at 02:06:10PM +0800, Herbert Xu wrote:
> On Wed, Nov 06, 2019 at 09:30:49AM +0000, Sverdlin, Alexander (Nokia - DE/Ulm) wrote:
> > From: Alexander Sverdlin <alexander.sverdlin@nokia.com>
> > 
> > Current polling timeout is 25 us. The hardware is currently configured to
> > harvest the entropy for 81920 us. This leads to timeouts even during
> > blocking read (wait=1).
> > 
> > Log snippet:
> > [    5.727589] [<c040ffcc>] (ks_sa_rng_probe) from [<c04181e8>] (platform_drv_probe+0x58/0xb4)
> > ...
> > [    5.727805] hwrng: no data available
> > ...
> > [   13.157016] random: systemd: uninitialized urandom read (16 bytes read)
> > [   13.157033] systemd[1]: Initializing machine ID from random generator.
> > ...
> > [   15.848770] random: fast init done
> > ...
> > [   15.848807] random: crng init done
> > 
> > After the patch:
> > [    6.223534] random: systemd: uninitialized urandom read (16 bytes read)
> > [    6.223551] systemd[1]: Initializing machine ID from random generator.
> > ...
> > [    6.876075] random: fast init done
> > ...
> > [    6.954200] random: systemd: uninitialized urandom read (16 bytes read)
> > [    6.955244] random: systemd: uninitialized urandom read (16 bytes read)
> > ...
> > [    7.121948] random: crng init done
> > 
> > Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
> > ---
> >  drivers/char/hw_random/ks-sa-rng.c | 38 ++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 38 insertions(+)
> 
> Patch applied.  Thanks.

This is causing a build error.  Seems that a line of the patch in
ks_sa_rng_init() went missing when it was applied...?

drivers/char/hw_random/ks-sa-rng.c: In function 'ks_sa_rng_init':
drivers/char/hw_random/ks-sa-rng.c:146:47: error: 'clk_rate' undeclared (first use in this function)
  146 |  ks_sa_rng->refill_delay_ns = refill_delay_ns(clk_rate);
      |                                               ^~~~~~~~
drivers/char/hw_random/ks-sa-rng.c:146:47: note: each undeclared identifier is reported only once for each function it appears in