From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97094C4CEC9 for ; Tue, 17 Sep 2019 12:40:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 71FCF2067B for ; Tue, 17 Sep 2019 12:40:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728153AbfIQMk2 (ORCPT ); Tue, 17 Sep 2019 08:40:28 -0400 Received: from helcar.hmeau.com ([216.24.177.18]:34036 "EHLO fornost.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728123AbfIQMk2 (ORCPT ); Tue, 17 Sep 2019 08:40:28 -0400 Received: from gwarestrin.arnor.me.apana.org.au ([192.168.0.7]) by fornost.hmeau.com with smtp (Exim 4.89 #2 (Debian)) id 1iACmL-0008IP-Ik; Tue, 17 Sep 2019 22:40:22 +1000 Received: by gwarestrin.arnor.me.apana.org.au (sSMTP sendmail emulation); Tue, 17 Sep 2019 22:40:18 +1000 Date: Tue, 17 Sep 2019 22:40:18 +1000 From: Herbert Xu To: Laurent Vivier Cc: linux-kernel@vger.kernel.org, Amit Shah , linux-crypto@vger.kernel.org, Matt Mackall Subject: Re: [PATCH] hw_random: don't wait on add_early_randomness() Message-ID: <20190917124018.GA32437@gondor.apana.org.au> References: <20190917095450.11625-1-lvivier@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190917095450.11625-1-lvivier@redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 17, 2019 at 11:54:50AM +0200, Laurent Vivier wrote: > add_early_randomness() is called by hwrng_register() when the > hardware is added. If this hardware and its module are present > at boot, and if there is no data available the boot hangs until > data are available and can't be interrupted. > > To avoid that, call rng_get_data() in non-blocking mode (wait=0) > from add_early_randomness(). > > Signed-off-by: Laurent Vivier > --- > drivers/char/hw_random/core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Please provide more context in your patch description such as which driver actually causes a hang here. Thanks, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt