From: Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: [PATCH 3.11-rc1] crypto: Fix boot failure due to module
 dependency.
Date: Sat, 20 Jul 2013 09:24:59 +1000
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Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Tim Chen <tim.c.chen@linux.intel.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
	linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org,
	ak <ak@linux.intel.com>,
	ACPI Devel Maling List <linux-acpi@vger.kernel.org>
To: "H. Peter Anvin" <hpa@zytor.com>
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On Fri, Jul 19, 2013 at 04:21:09PM -0700, H. Peter Anvin wrote:
>
> The issue here seems to be the dynamic binding nature of the crypto
> subsystem.  When something needs crypto, it will request the appropriate
> crypto module (e.g. crct10dif), which may race with detecting a specific
> hardware accelerator based on CPUID or device information (e.g.
> crct10dif_pclmul).
> 
> RAID has effectively the same issue, and we just "solved" it by
> compiling in all the accelerators into the top-level module.

I think for crypto the simplest solution is to not do CPUID-based
loading.  Then crypto users will simply load the module alias which
causes modprobe to load all modules providing that alias.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt