From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id F2C7C7D2EF for ; Fri, 7 Jun 2019 08:07:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727051AbfFGIHT (ORCPT ); Fri, 7 Jun 2019 04:07:19 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:60444 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726725AbfFGIHT (ORCPT ); Fri, 7 Jun 2019 04:07:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=KMTOjZOt6BKNdwNx8Ebfe50Na45GQkzWalc7XXT6zV4=; b=gUrzDU4WY3ZDbo8lcxgsikvBt Gk/hCRgMJufxg1JP0EiHMgv3rW3FTF5YlIOF5lwojw0Vtmugp/lHlLizM9NRf/e3yKeUqmCd0Zemq zx8uNPPPRNfImn+2IFgekQpgFW1/oQy/S2EESOhkYQM/IXXSqv4E/3YDd8nQU8v05iO7ozzW4EGPN fwb++MbbuniaJF04HclowhKkT/iaHsGrLExCsLo9SQgROaxNItKKT3ETdE49oHREjTn6pPBhFJtEg uAOrOlsb7mWX4fTtopbZirLCbiKs5iuYoa0qGCa8QrZ2hgGEm4z7mb3ANt1nwEQJW5cusG+tB+kxh 58BwvwZHg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hZ9tz-00013c-Mi; Fri, 07 Jun 2019 08:07:08 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 387A1202CD6B2; Fri, 7 Jun 2019 10:07:06 +0200 (CEST) Date: Fri, 7 Jun 2019 10:07:06 +0200 From: Peter Zijlstra To: Yu-cheng Yu 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 , Borislav Petkov , 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 , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin Subject: Re: [PATCH v7 07/14] x86/cet/ibt: Add arch_prctl functions for IBT Message-ID: <20190607080706.GS3419@hirez.programming.kicks-ass.net> References: <20190606200926.4029-1-yu-cheng.yu@intel.com> <20190606200926.4029-8-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190606200926.4029-8-yu-cheng.yu@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Thu, Jun 06, 2019 at 01:09:19PM -0700, Yu-cheng Yu wrote: > +static int handle_bitmap(unsigned long arg2) > +{ > + unsigned long addr, size; > + > + if (get_user(addr, (unsigned long __user *)arg2) || > + get_user(size, (unsigned long __user *)arg2 + 1)) > + return -EFAULT; > + > + return cet_setup_ibt_bitmap(addr, size); > +} > + /* > + * Allocate legacy bitmap and return address & size to user. > + */ > + case ARCH_X86_CET_SET_LEGACY_BITMAP: > + return handle_bitmap(arg2); AFAICT it does exactly the opposite of that comment; it gets the address and size from userspace and doesn't allocate anything at all.