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Date:   Wed, 6 Jul 2022 14:23:31 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     "H. Peter Anvin" <hpa@zytor.com>
Cc:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        linux-arm-kernel@lists.infradead.org,
        linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Heiko Carstens <hca@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] random: remove CONFIG_ARCH_RANDOM and "nordrand"
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On Tue, Jul 05, 2022 at 04:11:45PM -0700, H. Peter Anvin wrote:
> What I'm wondering is if we shouldn't be simply instrument *every*
> invocation, and set the trust to zero if we ever trip it.

I guess you can add some logic to rdrand_long() to sanity-check what it
returns...

But would that be worth the effort?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette