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=-5.8 required=3.0 tests=BAYES_00,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 55D67C433DB for ; Fri, 19 Mar 2021 09:28:11 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BE32264F62 for ; Fri, 19 Mar 2021 09:28:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE32264F62 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 506DC6B0072; Fri, 19 Mar 2021 05:28:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4B4BA6B0073; Fri, 19 Mar 2021 05:28:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 355F56B0074; Fri, 19 Mar 2021 05:28:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0155.hostedemail.com [216.40.44.155]) by kanga.kvack.org (Postfix) with ESMTP id 1357A6B0072 for ; Fri, 19 Mar 2021 05:28:10 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id C5A78180268DF for ; Fri, 19 Mar 2021 09:28:09 +0000 (UTC) X-FDA: 77936097498.10.0BA9A7E Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf13.hostedemail.com (Postfix) with ESMTP id 179E9E0001AF for ; Fri, 19 Mar 2021 09:28:08 +0000 (UTC) Received: from zn.tnic (p200300ec2f091e00ccf0bdf306f8eebc.dip0.t-ipconnect.de [IPv6:2003:ec:2f09:1e00:ccf0:bdf3:6f8:eebc]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 3FBE41EC0598; Fri, 19 Mar 2021 10:28:07 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1616146087; 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:in-reply-to:in-reply-to: references:references; bh=x5iZs50qGLJl3wWJ6Z8Q/HzduN81imNbW0pU6JloYuo=; b=h9c+OWSFsKDiriwZ4T3n4NNMY19803vt4GuW/AcaffbPxaSNUfNucDuudBqw1YPqk5BYqz sVoCdpmAtrWjKbk7Y/cMI1PahAmEIY49jZAhreJVMI3B8oH1aWYVvsgzIewg+mmcuDlTV+ 3Sw5pKWCvU+z2Xj55irdKup90tXAYFU= Date: Fri, 19 Mar 2021 10:28:06 +0100 From: Borislav Petkov To: "Yu, Yu-cheng" Cc: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang Subject: Re: [PATCH v23 22/28] x86/cet/shstk: User-mode shadow stack support Message-ID: <20210319092806.GB6251@zn.tnic> References: <20210316151054.5405-1-yu-cheng.yu@intel.com> <20210316151054.5405-23-yu-cheng.yu@intel.com> <20210318123215.GE19570@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 179E9E0001AF X-Stat-Signature: met4uxxhner5xsaksthnqpwx4n6f5nwe Received-SPF: none (alien8.de>: No applicable sender policy available) receiver=imf13; identity=mailfrom; envelope-from=""; helo=mail.skyhub.de; client-ip=5.9.137.197 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616146088-626652 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Mar 18, 2021 at 12:05:58PM -0700, Yu, Yu-cheng wrote: > Maybe I would add comments here. Yap. Also, looking forward in the set, I see prctl_set() and that is also done on current so should be ok. In any case, yes, documenting the assumptions and expectations wrt current here is a good idea. > If vm_munmap() returns -EINTR, mmap_lock is held by something else. That > lock should not be held forever. For other types of error, the loop stops. Ok I guess. The subsequent WARN_ON_ONCE() looks weird too but that should not fire, right? :) Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette