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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 E75F2C433DF for ; Tue, 28 Jul 2020 11:02:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B459B204EA for ; Tue, 28 Jul 2020 11:02:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VcuHUzhC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728863AbgG1LCC (ORCPT ); Tue, 28 Jul 2020 07:02:02 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:52298 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728688AbgG1LCC (ORCPT ); Tue, 28 Jul 2020 07:02:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595934120; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XNR5WY2cWDahy2gyeJK0kb6s2X+lgnpqYhuDhcd8ew8=; b=VcuHUzhCv0/HWuzPt8up0AR2UeTOBbBjktdG4yO7Ov4wl/oVBsN2+k+me6VID71/RJc/k7 59KOjHfmxEyn1xWkbMCrzKxaOnq1gCnMWnAIZWdqe8mi5XNriFjTKEh61WBeH3cpQXs88V KuEYubyKip3w8zYulatcdJdQzcqKXEc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-13-kajcVqc3M8WsewvTSNVy_w-1; Tue, 28 Jul 2020 07:01:56 -0400 X-MC-Unique: kajcVqc3M8WsewvTSNVy_w-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4551010059AC; Tue, 28 Jul 2020 11:01:54 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-112-32.rdu2.redhat.com [10.10.112.32]) by smtp.corp.redhat.com (Postfix) with ESMTP id C1518712F6; Tue, 28 Jul 2020 11:01:51 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <202007211144.A68C31D@keescook> References: <202007211144.A68C31D@keescook> <202006142054.C00B3E9C9@keescook> <20200612183450.4189588-1-keescook@chromium.org> <7be4d56b-0406-099b-e505-02e074c5173e@huawei.com> <544539.1595328664@warthog.procyon.org.uk> To: Kees Cook Cc: dhowells@redhat.com, Xiaoming Ni , Peter Zijlstra , David Windsor , Hans Liljestrand , Elena Reshetova , Paul Moore , edumazet@google.com, paulmck@kernel.org, shakeelb@google.com, James Morris , alex.huangjianhui@huawei.com, dylix.dailei@huawei.com, chenzefeng2@huawei.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/3] Convert nsproxy, groups, and creds to refcount_t MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <3212524.1595934111.1@warthog.procyon.org.uk> Content-Transfer-Encoding: quoted-printable Date: Tue, 28 Jul 2020 12:01:51 +0100 Message-ID: <3212525.1595934111@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Kees Cook wrote: > > I've been gradually undoing some of the conversions as there's no equi= valent > > of atomic_add_return() and atomic_dec_return() that allow me to log th= e > > altered refcount through a tracepoint. > = > Please do not _undo_ the changes; just add the API you need. And _please_ do not convert atomic_inc/dec_return() into refcount_read() + refcount_xxx(). They are _not_ equivalent. David