Linux cryptographic layer development
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From: Gary R Hook <gary.hook@amd.com>
To: Theodore Ts'o <tytso@mit.edu>, Oliver Mangold <o.mangold@gmail.com>
Cc: "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>
Subject: Re: Poor RNG performance on Ryzen
Date: Fri, 21 Jul 2017 10:04:16 -0500	[thread overview]
Message-ID: <842a138e-ff8f-4a2a-0bbe-3e419b008d65@amd.com> (raw)
In-Reply-To: <20170721144741.4igkvsd2fowptsy2@thunk.org>

On 07/21/2017 09:47 AM, Theodore Ts'o wrote:
> On Fri, Jul 21, 2017 at 01:39:13PM +0200, Oliver Mangold wrote:
>> Better, but obviously there is still much room for improvement by reducing
>> the number of calls to RDRAND.
>
> Hmm, is there some way we can easily tell we are running on Ryzen?  Or
> do we believe this is going to be true for all AMD devices?
>
> I guess we could add some kind of "has_crappy_arch_get_random()" call
> which could be defined by arch/x86, and change how aggressively we use
> arch_get_random_*() depending on whether has_crappy_arch_get_random()
> returns true or not....

Just a quick note to say that we are aware of the issue, and that it is
being addressed.

  parent reply	other threads:[~2017-07-21 15:04 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-21  7:12 Poor RNG performance on Ryzen Oliver Mangold
2017-07-21  9:26 ` Jan Glauber
2017-07-21 11:39   ` Oliver Mangold
2017-07-21 14:47     ` Theodore Ts'o
2017-07-21 14:55       ` Oliver Mangold
2017-07-22 18:16         ` Theodore Ts'o
2017-07-25  6:20           ` Jan Glauber
2017-07-21 15:04       ` Gary R Hook [this message]
2017-07-21 12:11 ` Jeffrey Walton

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