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From: Stephan Mueller <smueller@chronox.de>
To: John Stultz <john.stultz@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>, Herbert Xu <herbert@gondor.apana.org.au>,
        Alexander Kuleshov <kuleshovmail@gmail.com>,
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        "David S. Miller" <davem@davemloft.net>,
        Kees Cook <keescook@chromium.org>
Subject: Re: [Y2038] [PATCH] crypto: use timespec64 for jent_get_nstime
Date: Tue, 21 Jun 2016 19:16:15 +0200
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Am Dienstag, 21. Juni 2016, 10:12:24 schrieb John Stultz:

Hi John,
> 
> So this is definitely more clear then what was described earlier, and
> worries me because on many x86 machines (though fewer I guess these
> days then in the past) the clocksource will often not be the TSC (and
> have lower resolution).

Please note, the use of the ktime_get_raw_ns() is *only* used as a fallback on 
architectures where random_get_entropy / get_cycles is not implemented.

So, on X86 and on many other arches, this function call will never be 
triggered.

...
> 
> But please just make sure the reason why you're using that specific
> interface is clearly documented in the code so we don't have to later
> reverse engineer the intent.

Will do.

@Arnd: I would prepare a patch then using ktime_get_raw_ns and providing a 
good documentation in the code.

Ciao
Stephan