Some AMD CPU's RDRAND might not return random data after a suspend/resume

Re:Some AMD CPU's RDRAND might not return random data after ... by zaroth on Wednesday May 08, 2019 @03:51PM (#19862249)

The Bugzilla report seemed to indicate that AMD was returning an error code, because OpenSSL was failing to generate a key, not generating a bad key?

Why would OpenSSL fail visibly if the API was returning success but with non-random data?

https://bugzilla.redhat.com/show_bug.cgi?id=1150286

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Re:Some AMD CPU's RDRAND might not return random data after ... by int_19h on Wednesday May 08, 2019 @11:31PM (#19865129)

If you look closely at one of the error messages, it says "too many iterations", in what looks like a random generator. I wonder if at some point it has to iterate to get a number different from another one, and it just gets an endless stream of identical values?

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Re:Some AMD CPU's RDRAND might not return random data after ... by zaroth on Wednesday May 08, 2019 @11:51PM (#19865212)

I can’t imagine the code is checking the returned value for uniqueness after seeing a SUCCESS code, and iterating in the hopes that becomes less true.

That would be quite something to read the comment on;

// Here we check to be sure the Earth is not flat

...

// Seeing that the Earth is indeed flat, we will iterate in this absurdity some more in the hopes it rounds out eventually

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Re:Some AMD CPU's RDRAND might not return random data after ... by int_19h on Thursday May 09, 2019 @04:11PM (#19871914)

Suppose you need to generate several unique 32-bit IDs for something?

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