Received: by 2002:a05:6a10:22f:0:0:0:0 with SMTP id 15csp799383pxk; Sat, 12 Sep 2020 00:10:59 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxiAqQ8PMWWZjDKdfiC5XQWw3wzB+8Q9b4lKXqlucZwWgMUNqefJpuEbSW0YHN4eIVsEyQM X-Received: by 2002:a17:907:6f6:: with SMTP id yh22mr5118072ejb.268.1599894659164; Sat, 12 Sep 2020 00:10:59 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1599894659; cv=none; d=google.com; s=arc-20160816; b=QSMcL/dBTeSionquOXpc82ERyKOJ740YABX2MRMzfd6chnYOZs/51+CG6igvzS82ep 4rcUbdBcNF95oVeKzAoIWEOx3rOAlfu189yJsx6TqTW54WKYeH554k8N1XArBngZ4Bwn e98cHlLzpQ3haTWXlh6pYHFfS/8CKpEvcRBDW7Dt4MPtnMYQKcHgArxzrxmqaSeNf7QW Qv/02Ei0hibHtjN0hsy8cgm6NUVlq6Qh3RmyYNZWAMBc9mH7jvffLYiX1FReKEkhsedS vx4i3Kc+/yQN7Ay0qIs76XX/6u27mF5fJNiSExCRtSr2vqu5QCtqOCfswE4SsA9awZbw Ac5Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=gW1ck+r1FAMElSp3y0oX4rgH8DSUMf1vdHyZeXkfF34=; b=A6labXR24pWjnvhWuwg4e1aV9SemN3BMiUKOvPUT74lBnb5AYJ092aWHJRRe7NCx0M HyqYoxk/EuGn1kcAncmoLMsyfyZ4yQZ4Q+fdaQ5ZtuKw7+nAy473rfvv5iX7+H64jn2w 9m6+ZY+71iu1vpxLRizghQJYOzMktAaALpUKrauR7e+GQjvGfp7nFyLSKVtYUTewWJrV FHS051Exx7o60fgEEXGxHOCVro8EK7gPJ01wGldTCsJ+XN9t7AwTX01Qxv5OfDGapT1Z TADVGpa6pzi+KzSX5s6gHxusL/nrtFi0HNjpkx35QrnhDkcaXYyk2dMCEp0KNJ344ba0 ZlRg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id m23si2734502ejo.333.2020.09.12.00.10.36; Sat, 12 Sep 2020 00:10:59 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725880AbgILHIH (ORCPT + 99 others); Sat, 12 Sep 2020 03:08:07 -0400 Received: from verein.lst.de ([213.95.11.211]:39054 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725800AbgILHIG (ORCPT ); Sat, 12 Sep 2020 03:08:06 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id CC3BF68B02; Sat, 12 Sep 2020 09:08:02 +0200 (CEST) Date: Sat, 12 Sep 2020 09:08:02 +0200 From: Christoph Hellwig To: Gabriel Krisman Bertazi Cc: luto@kernel.org, tglx@linutronix.de, hpa@zytor.com, bp@alien8.de, rric@kernel.org, peterz@infradead.org, mingo@redhat.com, x86@kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Christoph Hellwig Subject: Re: [PATCH 2/6] x86: Simplify compat syscall userspace allocation Message-ID: <20200912070802.GA19621@lst.de> References: <20200912070553.330622-1-krisman@collabora.com> <20200912070553.330622-3-krisman@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200912070553.330622-3-krisman@collabora.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 12, 2020 at 03:05:49AM -0400, Gabriel Krisman Bertazi wrote: > When allocating user memory space for a compat system call, don't > consider whether the originating code is IA32 or X32, just allocate from > a safe region for both, beyond the redzone. This should be safe for > IA32, and has the benefit of avoiding TIF_IA32, which we want to drop. This doesn't look wrong, by why bother (maybe Ccing me on the whole seris as you always should instead of sending annoying out of context single patches would have told..). We will hopefully kill off compat_alloc_user_space in the next few merge windows..