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=-8.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 75ADFC2D0DB for ; Wed, 29 Jan 2020 16:02:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C73D20716 for ; Wed, 29 Jan 2020 16:02:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ueJ6r87y" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726599AbgA2QCO (ORCPT ); Wed, 29 Jan 2020 11:02:14 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:33199 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726564AbgA2QCN (ORCPT ); Wed, 29 Jan 2020 11:02:13 -0500 Received: by mail-pg1-f196.google.com with SMTP id 6so9067226pgk.0; Wed, 29 Jan 2020 08:02:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=k8mHbmQQsrXwIuxRQsm7SslFnT6vNFl5PlAX5KpkYSQ=; b=ueJ6r87yt1XMC7LlrQYQKxOSAAX09m036BtYkdjlMPVSTIc9L5e/GrpfSdgYh7yz5N dHpTkWQFk445H92oj8dND7X+f8wPxXHtnCdMO8vXgpbBEfQR5QMXPI+sTRNDCWL6K5zJ 0dRGGepvfo0htl11QbrfHI72cNfdlqablwjouQsP34mO6kASH9MmI923RLjPDcQY/KtP 6KPayDh5Opilunyh8ZF5NLS9mBSH+Uc7Lg/7plRx94f+jZHgNYbY7cAwosX+qX3pR9Ii z4YtQn+zVsq5eTaS87NXNR6U8DV6jAWfw7r6R4T74Gr8nc0WEAZwMGQJ6JTM7RjQQ/0F V1aQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=k8mHbmQQsrXwIuxRQsm7SslFnT6vNFl5PlAX5KpkYSQ=; b=PUJlKp2HM1ip50aSC/sUpdwbbmtVFHe24ovuxWMqsZOx554DhbfcAkcA6iPIr1TOhn k12jrzNiSpSBHKOavaAoZz0oXN/TOsq1G80CcMDlo+tnPVipaRdZqtSxYFc2sFw4y+Jb gLgakZe+ZVsxdbjrnrQe90NdkQb2zD5LNCl8vHVOmcVKGoF18Fv5CiWK1ByU32iXs+nI vm89Ykn7WJNuIgPlI7dPgIgs85nNRaeC+SyNeG8hZs3c1eEioyb29GXn2/yaxcrp21ci Q4mwQxyRFYR5i3cXfmsnzA3upAOGt5FVUaw+O3qTQL2qMFIKgtEqGxYTLLxtprqM8NZC 43nA== X-Gm-Message-State: APjAAAX+8yzS7oZiZTjFMAODw1a8UcFlRlAyteTt9Vls+mzxegdrowMs 1xnG/5LmC4OQ7IATPPaEfQ== X-Google-Smtp-Source: APXvYqzrD+7oSyDpZl9ImkaISh0MgIPrwKGmgL0z/k1vQvBM6d+UcE9172zZWN39NOmWegWjZopjRA== X-Received: by 2002:aa7:800e:: with SMTP id j14mr275989pfi.174.1580313733106; Wed, 29 Jan 2020 08:02:13 -0800 (PST) Received: from madhuparna-HP-Notebook ([2402:3a80:1ee5:e7da:cc5e:c7d9:2a24:390]) by smtp.gmail.com with ESMTPSA id z30sm3274298pff.131.2020.01.29.08.02.08 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 29 Jan 2020 08:02:12 -0800 (PST) From: Madhuparna Bhowmik X-Google-Original-From: Madhuparna Bhowmik Date: Wed, 29 Jan 2020 21:32:04 +0530 To: Oleg Nesterov Cc: madhuparnabhowmik10@gmail.com, peterz@infradead.org, mingo@kernel.org, christian.brauner@ubuntu.com, paulmck@kernel.org, linux-kernel@vger.kernel.org, joel@joelfernandes.org, linux-kernel-mentees@lists.linuxfoundation.org, rcu@vger.kernel.org Subject: Re: [PATCH] exit.c: Fix Sparse errors and warnings Message-ID: <20200129160204.GA15449@madhuparna-HP-Notebook> References: <20200128172008.22665-1-madhuparnabhowmik10@gmail.com> <20200129123046.GA1726@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200129123046.GA1726@redhat.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: rcu-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org On Wed, Jan 29, 2020 at 01:30:47PM +0100, Oleg Nesterov wrote: > On 01/28, madhuparnabhowmik10@gmail.com wrote: > > > > kernel/exit.c:626:40: warning: incorrect type in assignment > > > > Signed-off-by: Madhuparna Bhowmik > > --- > > kernel/exit.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/exit.c b/kernel/exit.c > > index bcbd59888e67..c5a9d6360440 100644 > > --- a/kernel/exit.c > > +++ b/kernel/exit.c > > @@ -623,8 +623,8 @@ static void forget_original_parent(struct task_struct *father, > > reaper = find_new_reaper(father, reaper); > > list_for_each_entry(p, &father->children, sibling) { > > for_each_thread(p, t) { > > - t->real_parent = reaper; > > - BUG_ON((!t->ptrace) != (t->parent == father)); > > + rcu_assign_pointer(t->real_parent, reaper); > > Another case when RCU_INIT_POINTER() makes more sense (although to me it > too looks confusing). We didn't modify the new parent. > Alright, I will resend this patch with RCU_INIT_POINTER(). Thank you, Madhuparna > Oleg. >