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Date:   Sat, 19 Nov 2022 12:43:31 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "patches@lists.linux.dev" <patches@lists.linux.dev>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
        Carlos O'Donell <carlos@redhat.com>
Subject: Re: [PATCH v4 2/3] random: introduce generic vDSO getrandom()
 implementation
Message-ID: <Y3jBY4p2hEKDaUm+@zx2c4.com>
References: <20221118172839.2653829-1-Jason@zx2c4.com>
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On Sat, Nov 19, 2022 at 07:51:21AM +0000, Christophe Leroy wrote:
> 
> 
> Le 19/11/2022 à 01:04, Jason A. Donenfeld a écrit :
> > On Sat, Nov 19, 2022 at 12:55:02AM +0100, Jason A. Donenfeld wrote:
> >> Sorry if I'm a bit slow here to grok what's up.
> 
> Maybe I should also have mentionned commit ce7d8056e38b ("powerpc/vdso: 
> Prepare for switching VDSO to generic C implementation.") for you to 
> have a complete picture.
> 
> > 
> > Okay, I think I see it now. That's a complicated patch for a simple idea
> > because gettime is more complicated than getrandom. I suspect what you
> > want is something like the below, correct? Seems easy enough.
> 
> Yes it is exactly that, powerpc will then call __cvdso_getrandom_data() 
> directly and pass rng_info pointer.

Okay, I'll do that and send out a v+1.

Jason