From: Herbert Xu Subject: Re: Initcall ordering problem (TTY vs modprobe vs MD5) and cryptomgr problem Date: Fri, 6 Aug 2010 10:35:39 +0800 Message-ID: <20100806023539.GA22774@gondor.apana.org.au> References: <23662.1281056463@redhat.com> <20100806011706.GA21657@gondor.apana.org.au> <20100806014057.GA22395@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Howells , gregkh@suse.de, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org To: Linus Torvalds Return-path: Received: from helcar.apana.org.au ([209.40.204.226]:33512 "EHLO fornost.hengli.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933390Ab0HFCfx (ORCPT ); Thu, 5 Aug 2010 22:35:53 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-crypto-owner@vger.kernel.org List-ID: On Thu, Aug 05, 2010 at 07:01:21PM -0700, Linus Torvalds wrote: > On Thu, Aug 5, 2010 at 6:40 PM, Herbert Xu wrote: > > > > -config CRYPTO_MANAGER_TESTS > > - =A0 =A0 =A0 bool "Run algolithms' self-tests" > > - =A0 =A0 =A0 default y > > - =A0 =A0 =A0 depends on CRYPTO_MANAGER2 > > +config CRYPTO_MANAGER_DISABLE_TESTS > > + =A0 =A0 =A0 bool "Disable run-time self tests" > > + =A0 =A0 =A0 depends on CRYPTO_MANAGER2 && EMBEDDED >=20 > Why do you still want to force-enable those tests? I was going to > complain about the "default y" anyway, now I'm _really_ complaining, > because you've now made it impossible to disable those tests. Why? Because it can save data. Each cryptographic algorithm (such as AES) may have multiple impelmentations, some of which are hardware- based. The purpose of these tests are to make a particular driver or implementation available only if it passes them. So your encrypted disk/file system will not be subject to a hardware/software combo without at least some semblance of testing. The last thing you want to is to upgrade your kernel with a new hardware crypto driver that detects that you have a piece of rarely- used crypto hardeware, decides to use it and ends up making your data toast. But whatever, if you want the default to be no tests, that's fine. Here's the patch to do just that. commit 00ca28a507b215dcd121735f16764ea4173c4ff9 Author: Herbert Xu Date: Fri Aug 6 10:34:00 2010 +0800 crypto: testmgr - Default to no tests =20 On Thu, Aug 05, 2010 at 07:01:21PM -0700, Linus Torvalds wrote: > On Thu, Aug 5, 2010 at 6:40 PM, Herbert Xu wrote: > > > > -config CRYPTO_MANAGER_TESTS > > - bool "Run algolithms' self-tests" > > - default y > > - depends on CRYPTO_MANAGER2 > > +config CRYPTO_MANAGER_DISABLE_TESTS > > + bool "Disable run-time self tests" > > + depends on CRYPTO_MANAGER2 && EMBEDDED > > Why do you still want to force-enable those tests? I was going to > complain about the "default y" anyway, now I'm _really_ complaini= ng, > because you've now made it impossible to disable those tests. Why= ? =20 As requested, this patch sets the default to y and removes the EMBEDDED dependency. =20 Signed-off-by: Herbert Xu diff --git a/crypto/Kconfig b/crypto/Kconfig index 6f5c50f..e573077 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -103,7 +103,8 @@ config CRYPTO_MANAGER2 =20 config CRYPTO_MANAGER_DISABLE_TESTS bool "Disable run-time self tests" - depends on CRYPTO_MANAGER2 && EMBEDDED + default y + depends on CRYPTO_MANAGER2 help Disable run-time self tests that normally take place at algorithm registration. Cheers, --=20 Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt