From: Andrey Borzenkov <arvidjaar@mail.ru>
To: linux-crypto@vger.kernel.org
Subject: Clarification of allowed context for crypto routines
Date: Fri, 23 Jan 2009 22:29:46 +0300
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According to Documentation/crypto/api-intro.txt:

DEVELOPER NOTES

Transforms may only be allocated in user context, and cryptographic
methods may only be called from softirq and user contexts.  For
transforms with a setkey method it too should only be called from
user context.

As I can understand, user context requirement is due to potential for=20
setkey to sleep (although it appears, that currently the only module=20
that can sleep is shash which is calling kmalloc with GFP_KERNEL). Is it=20
correct?

But where is the difference between hard and softirq contexts? I fail to=20
see any technical reason for this requirement.

Thank you!

=2Dandrey

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