From: Herbert Xu Subject: Re: crypto_shash_update & CRYPTO_TFM_REQ_MAY_SLEEP Date: Tue, 9 Feb 2010 18:41:46 +1100 Message-ID: <20100209074146.GA17681@gondor.apana.org.au> References: <4B69B07D.9010909@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-crypto@vger.kernel.org To: Dmitry Kasatkin Return-path: Received: from rhun.apana.org.au ([64.62.148.172]:39669 "EHLO arnor.apana.org.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752934Ab0BIHls (ORCPT ); Tue, 9 Feb 2010 02:41:48 -0500 Content-Disposition: inline In-Reply-To: <4B69B07D.9010909@nokia.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: Dmitry Kasatkin wrote: > > One interesting issue > > Many clients in the kernel set CRYPTO_TFM_REQ_MAY_SLEEP to desc.flags. > It is used by crypto_yeld(). That flag is really only meaningful for synchronous implementations. For hardware crypto that is asynchronous, you can simply ignore it in most cases (exceptions include invoking a syncrhonous backup, for example). Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt