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From:   Stephan Mueller <smueller@chronox.de>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Palmer Dabbelt <palmerdabbelt@google.com>,
        linux-riscv <linux-riscv@lists.infradead.org>,
        Android Kernel Team <kernel-team@android.com>,
        kernel test robot <lkp@intel.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] crypto: jitterentropy - bind statically into kernel
Date:   Mon, 05 Oct 2020 09:45:33 +0200
Message-ID: <2961600.L5xXbe6F5v@tauon.chronox.de>
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References: <20200930065617.934638-1-palmerdabbelt@google.com> <2588700.mWSkj6HvKX@tauon.chronox.de> <CAMj1kXFL4gfrK1+zRG9sajTk62yRh3WzBG46KfKD=iM=VQMTAQ@mail.gmail.com>
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Am Montag, 5. Oktober 2020, 08:44:39 CEST schrieb Ard Biesheuvel:

Hi Ard,

> On Mon, 5 Oct 2020 at 08:40, Stephan Mueller <smueller@chronox.de> wrote:
> > Am Montag, 5. Oktober 2020, 08:24:46 CEST schrieb Ard Biesheuvel:
> > 
> > Hi Ard,
> > 
> > > If jitterentropy is a special case, we could put a alternate
> > > non-'static inline' version of random_get_entropy() in the core
> > > kernel, and only export it if JITTER_ENTROPY is built as a module in
> > > the first place. But I'd prefer it if jitterentropy switches to an API
> > > that is suitable for driver consumption.
> > 
> > Which API do you have in mind? In user space, I use
> > clock_gettime(CLOCK_REALTIME) which also considers the clock source.
> 
> AFAICT, that call is backed by ktime_get_real_ts64(), which is already
> being exported to modules.
> 
> Could you please check whether that works for your driver?

Yes, will do. Thanks.

Ciao
Stephan