From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C817771 for ; Wed, 12 May 2021 16:00:34 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 7621E247; Wed, 12 May 2021 18:00:32 +0200 (CEST) Date: Wed, 12 May 2021 18:00:31 +0200 From: Joerg Roedel To: Dave Hansen Cc: x86@kernel.org, Hyunwook Baek , Joerg Roedel , stable@vger.kernel.org, hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , Arvind Sankar , linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: Re: [PATCH 3/6] x86/sev-es: Use __put_user()/__get_user Message-ID: References: <20210512075445.18935-1-joro@8bytes.org> <20210512075445.18935-4-joro@8bytes.org> <9282239c-138c-7226-88d3-a5611d11cccd@intel.com> X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9282239c-138c-7226-88d3-a5611d11cccd@intel.com> On Wed, May 12, 2021 at 08:57:53AM -0700, Dave Hansen wrote: > The changelog _helps_, but using a "user" function to handle kernel MMIO > for its error handling properties seems like it's begging for a comment. > > __put_user() also seems to have fun stuff like __chk_user_ptr(). It all > seems sketchy to me. Yeah, as Juergen already pointed out, there are certain problems with that too. But I don't want to write my own accessors, so I will introduce a separate user and kernel path to these functions. Regards, Joerg 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=-3.8 required=3.0 tests=BAYES_00, 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 E804AC433B4 for ; Wed, 12 May 2021 16:00:39 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 4A0BB61E0B for ; Wed, 12 May 2021 16:00:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4A0BB61E0B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id D724E4018F; Wed, 12 May 2021 16:00:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QQrLpeU42ypv; Wed, 12 May 2021 16:00:38 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp2.osuosl.org (Postfix) with ESMTP id 8B275401FF; Wed, 12 May 2021 16:00:37 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 6786AC000E; Wed, 12 May 2021 16:00:37 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 26C28C0001 for ; Wed, 12 May 2021 16:00:37 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 144F4404BE for ; Wed, 12 May 2021 16:00:37 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gbeX8NgCwj5m for ; Wed, 12 May 2021 16:00:36 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp4.osuosl.org (Postfix) with ESMTPS id 33AD6404B8 for ; Wed, 12 May 2021 16:00:36 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 7621E247; Wed, 12 May 2021 18:00:32 +0200 (CEST) Date: Wed, 12 May 2021 18:00:31 +0200 From: Joerg Roedel To: Dave Hansen Subject: Re: [PATCH 3/6] x86/sev-es: Use __put_user()/__get_user Message-ID: References: <20210512075445.18935-1-joro@8bytes.org> <20210512075445.18935-4-joro@8bytes.org> <9282239c-138c-7226-88d3-a5611d11cccd@intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <9282239c-138c-7226-88d3-a5611d11cccd@intel.com> Cc: kvm@vger.kernel.org, Peter Zijlstra , Dave Hansen , virtualization@lists.linux-foundation.org, Arvind Sankar , hpa@zytor.com, Jiri Slaby , x86@kernel.org, David Rientjes , Martin Radev , Tom Lendacky , Joerg Roedel , Kees Cook , Cfir Cohen , Hyunwook Baek , linux-coco@lists.linux.dev, Andy Lutomirski , Dan Williams , Juergen Gross , Mike Stunes , Sean Christopherson , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Masami Hiramatsu , Erdem Aktas X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Wed, May 12, 2021 at 08:57:53AM -0700, Dave Hansen wrote: > The changelog _helps_, but using a "user" function to handle kernel MMIO > for its error handling properties seems like it's begging for a comment. > > __put_user() also seems to have fun stuff like __chk_user_ptr(). It all > seems sketchy to me. Yeah, as Juergen already pointed out, there are certain problems with that too. But I don't want to write my own accessors, so I will introduce a separate user and kernel path to these functions. Regards, Joerg _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization