From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754526AbaC0IxG (ORCPT ); Thu, 27 Mar 2014 04:53:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60847 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752864AbaC0IxD (ORCPT ); Thu, 27 Mar 2014 04:53:03 -0400 Message-ID: <5333E6E3.3020907@redhat.com> Date: Thu, 27 Mar 2014 09:52:51 +0100 From: Daniel Borkmann User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Sasha Levin CC: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, hannes@stressinduktion.org, tytso@mit.edu Subject: Re: [PATCH v2] random32: avoid attempt to late reseed if in the middle of seeding References: <1395900095-15254-1-git-send-email-sasha.levin@oracle.com> <1395900095-15254-2-git-send-email-sasha.levin@oracle.com> In-Reply-To: <1395900095-15254-2-git-send-email-sasha.levin@oracle.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/27/2014 07:01 AM, Sasha Levin wrote: > Commit 4af712e8df ("random32: add prandom_reseed_late() and call when > nonblocking pool becomes initialized") has added a late reseed stage > that happens as soon as the nonblocking pool is marked as initialized. > > This fails in the case that the nonblocking pool gets initialized > during __prandom_reseed()'s call to get_random_bytes(). In that case > we'd double back into __prandom_reseed() in an attempt to do a late > reseed - deadlocking on 'lock' early on in the boot process. > > Instead, just avoid even waiting to do a reseed if a reseed is already > occuring. > > Signed-off-by: Sasha Levin Looks better now, thanks! Fixes: 4af712e8df99 ("random32: add prandom_reseed_late() and call when nonblocking pool becomes initialized") Acked-by: Daniel Borkmann