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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 E1984C7618F for ; Thu, 18 Jul 2019 14:56:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE03C21851 for ; Thu, 18 Jul 2019 14:56:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390724AbfGRO4t (ORCPT ); Thu, 18 Jul 2019 10:56:49 -0400 Received: from helcar.hmeau.com ([216.24.177.18]:52432 "EHLO deadmen.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727762AbfGRO4s (ORCPT ); Thu, 18 Jul 2019 10:56:48 -0400 Received: from gondobar.mordor.me.apana.org.au ([192.168.128.4] helo=gondobar) by deadmen.hmeau.com with esmtps (Exim 4.89 #2 (Debian)) id 1ho7pl-0000NL-DQ; Thu, 18 Jul 2019 22:56:37 +0800 Received: from herbert by gondobar with local (Exim 4.89) (envelope-from ) id 1ho7pi-0006Id-9i; Thu, 18 Jul 2019 22:56:34 +0800 Date: Thu, 18 Jul 2019 22:56:34 +0800 From: Herbert Xu To: Daniel Jordan Cc: Steffen Klassert , Andrea Parri , Boqun Feng , "Paul E . McKenney" , Peter Zijlstra , linux-arch@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Mathias Krause Subject: Re: [PATCH] padata: Replace delayed timer with immediate workqueue in padata_reorder Message-ID: <20190718145634.xagjemdqpoe44xxh@gondor.apana.org.au> References: <20190716163253.24377-1-daniel.m.jordan@oracle.com> <20190717111147.t776zlyhdqyl5dhc@gondor.apana.org.au> <20190717183227.b3hqphukkndqumhw@ca-dmjordan1.us.oracle.com> <20190718033131.4m4ypbq7tiucqcsl@gondor.apana.org.au> <20190718142730.uhdkwx5onigdpxno@ca-dmjordan1.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190718142730.uhdkwx5onigdpxno@ca-dmjordan1.us.oracle.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 18, 2019 at 10:27:30AM -0400, Daniel Jordan wrote: > > That's what I expected when I first saw it too, but nr_cpumask_bits is returned > to signal the end of the iteration. The patch always passes 0 for the 'start' > argument, so when cpumask_next_wrap is called with the last cpu in the mask, > the end-of-iteration case is triggered. To reassure you and myself :) I ran it > and got the expected crash. > > Passing pd->cpu for the start argument instead avoids that problem, but the > one-cpu-in-mask case still needs handling because cpumask_next_wrap always > signals end of iteration for that, hence the cpumask_weight check. My bad. I should have set start to -1 to make it do the right thing. Thanks, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt