Messages in this thread | | | Date | Mon, 5 Dec 2022 22:41:22 +0100 | From | "Jason A. Donenfeld" <> | Subject | Re: [PATCH v2 2/3] hwrng: add Rockchip SoC hwrng driver |
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Hi Aurelien,
On Mon, Dec 05, 2022 at 10:34:54PM +0100, Aurelien Jarno wrote: > Well I am not sure it really matters. 90% is actually conservative, it's > the worst case I have seen, rounded down. However I often get much > better quality, see for instance the following run: > > | Copyright (c) 2004 by Henrique de Moraes Holschuh > | This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. > | > | rngtest: starting FIPS tests... > | rngtest: entropy source drained > | rngtest: bits received from input: 16777216 > | rngtest: FIPS 140-2 successes: 819 > | rngtest: FIPS 140-2 failures: 19 > | rngtest: FIPS 140-2(2001-10-10) Monobit: 17 > | rngtest: FIPS 140-2(2001-10-10) Poker: 0 > | rngtest: FIPS 140-2(2001-10-10) Runs: 2 > | rngtest: FIPS 140-2(2001-10-10) Long run: 2 > | rngtest: FIPS 140-2(2001-10-10) Continuous run: 0 > | rngtest: input channel speed: (min=132.138; avg=137.848; max=147.308)Kibits/s > | rngtest: FIPS tests speed: (min=16.924; avg=20.272; max=20.823)Mibits/s > | rngtest: Program run time: 119647459 microseconds > > Does the exact value has an importance there? I thought it was just > important to not overestimate the quality.
That's the right principle. I just worry about estimating it like that from looking at the output, rather than being derived from some knowledge about the hardware. Maybe 50% (quality=512) is more reasonable, so that it collects two bits for every one?
Jason
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