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=-2.3 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 A5AE8C2BA19 for ; Mon, 6 Apr 2020 13:12:24 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 134B922456 for ; Mon, 6 Apr 2020 13:12:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 134B922456 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48wrYK0gsfzDqZR for ; Mon, 6 Apr 2020 23:12:21 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48wrMd3XpkzDqNg for ; Mon, 6 Apr 2020 23:03:56 +1000 (AEST) Received: by verein.lst.de (Postfix, from userid 2407) id 933A768BEB; Mon, 6 Apr 2020 15:03:51 +0200 (CEST) Date: Mon, 6 Apr 2020 15:03:51 +0200 From: Christoph Hellwig To: Al Viro Subject: Re: [PATCH 3/6] binfmt_elf: remove the set_fs(KERNEL_DS) in elf_core_dump Message-ID: <20200406130351.GA16479@lst.de> References: <20200406120312.1150405-1-hch@lst.de> <20200406120312.1150405-4-hch@lst.de> <20200406130238.GT23230@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200406130238.GT23230@ZenIV.linux.org.uk> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Arnd Bergmann , linux-kernel@vger.kernel.org, Jeremy Kerr , linux-fsdevel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, Christoph Hellwig Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Apr 06, 2020 at 02:02:38PM +0100, Al Viro wrote: > On Mon, Apr 06, 2020 at 02:03:09PM +0200, Christoph Hellwig wrote: > > There is no logic in elf_core_dump itself that uses uaccess routines > > on kernel pointers, the file writes are nicely encapsulated in dump_emit > > which does its own set_fs. > > ... assuming you've checked the asm/elf.h to see that nobody is playing > silly buggers in these forests of macros and the stuff called from those. > Which is a feat that ought to be mentioned in commit message... None of the calls should go into asm/elf.h headers, but some go to various out of line arch callouts. And I did look through those - spufs was the only funky one.