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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 AFCCAC282CE for ; Wed, 22 May 2019 16:24:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7EA0520675 for ; Wed, 22 May 2019 16:24:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729963AbfEVQYx (ORCPT ); Wed, 22 May 2019 12:24:53 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:42668 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729475AbfEVQYx (ORCPT ); Wed, 22 May 2019 12:24:53 -0400 Received: from callcc.thunk.org (guestnat-104-133-0-109.corp.google.com [104.133.0.109] (may be forged)) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id x4MGOiAF001557 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 May 2019 12:24:45 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 528AF420481; Wed, 22 May 2019 12:24:44 -0400 (EDT) Date: Wed, 22 May 2019 12:24:44 -0400 From: "Theodore Ts'o" To: kernel test robot Cc: linux-kernel@vger.kernel.org, LKP Subject: Re: eb9d1bf079 [ 88.881528] EIP: _random_read Message-ID: <20190522162444.GB2744@mit.edu> Mail-Followup-To: Theodore Ts'o , kernel test robot , linux-kernel@vger.kernel.org, LKP References: <20190516071405.GO31424@shao2-debian> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190516071405.GO31424@shao2-debian> 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 Can you check and see if this addresses the issue? I'm not able to easily repro the softlockup. Thanks! - Ted commit f93d3e94983bf8b4697ceb121c79afd941862860 Author: Theodore Ts'o Date: Wed May 22 12:02:16 2019 -0400 random: fix soft lockup when trying to read from an uninitialized blocking pool Fixes: eb9d1bf079bb: "random: only read from /dev/random after its pool has received 128 bits" Reported-by: kernel test robot Signed-off-by: Theodore Ts'o diff --git a/drivers/char/random.c b/drivers/char/random.c index a42b3d764da8..9cea93d0bfb3 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1936,8 +1936,8 @@ _random_read(int nonblock, char __user *buf, size_t nbytes) return -EAGAIN; wait_event_interruptible(random_read_wait, - ENTROPY_BITS(&input_pool) >= - random_read_wakeup_bits); + blocking_pool.initialized && + (ENTROPY_BITS(&input_pool) >= random_read_wakeup_bits)); if (signal_pending(current)) return -ERESTARTSYS; }