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Date:   Tue, 8 Nov 2022 12:00:40 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
Cc:     herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org,
        Dominik Brodowski <linux@dominikbrodowski.net>
Subject: Re: [PATCH v3] hw_random: use add_hwgenerator_randomness() for early
 entropy
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References: <Y2fJy1akGIdQdH95@zx2c4.com>
 <20221106150243.150437-1-Jason@zx2c4.com>
 <1839f462-dccb-b926-1acd-f1bb5f5776ba@collabora.com>
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On Tue, Nov 08, 2022 at 11:53:23AM +0100, AngeloGioacchino Del Regno wrote:
> Il 06/11/22 16:02, Jason A. Donenfeld ha scritto:
> > Rather than calling add_device_randomness(), the add_early_randomness()
> > function should use add_hwgenerator_randomness(), so that the early
> > entropy can be potentially credited, which allows for the RNG to
> > initialize earlier without having to wait for the kthread to come up.
> > 
> > This requires some minor API refactoring, by adding a `sleep_after`
> > parameter to add_hwgenerator_randomness(), so that we don't hit a
> > blocking sleep from add_early_randomness().
> > 
> > Cc: Herbert Xu <herbert@gondor.apana.org.au>
> > Cc: Dominik Brodowski <linux@dominikbrodowski.net>
> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
> > ---
> > Herbert - it might be easiest for me to take this patch if you want? Or
> > if this will interfere with what you have going on, you can take it. Let
> > me know what you feel like. -Jason
> > 
> >   drivers/char/hw_random/core.c |  8 +++++---
> >   drivers/char/random.c         | 12 ++++++------
> >   include/linux/random.h        |  2 +-
> >   3 files changed, 12 insertions(+), 10 deletions(-)
> > 
> 
> Hello,
> 
> I tried booting next-20221108 on Acer Tomato Chromebook (MediaTek MT8195) but
> this commit is producing a kernel panic.


Thanks for the report. I see exactly what the problem is, and I'll send
a v+1 right away.

Jason