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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 9A0A2C433E0 for ; Thu, 14 May 2020 12:27:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 665A120722 for ; Thu, 14 May 2020 12:27:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="u+lnrCuC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726216AbgENM1l (ORCPT ); Thu, 14 May 2020 08:27:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725955AbgENM1l (ORCPT ); Thu, 14 May 2020 08:27:41 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33880C061A0C for ; Thu, 14 May 2020 05:27:41 -0700 (PDT) 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; bh=aA5M/XpaRV+Oml4TIMxh30lFTbOlhWVBMWNdlNQaq7w=; b=u+lnrCuCpJW0P9fqCJ9vD5pQI7 ArUpPU4ofZ1iu8SrNSHp6Ml4DI1vQ35tM3hOTouwLdXXr1TJHZeOPX/fzWEzrOjnbSJNJEOWYRd+N sET5/QxruF4X2BTxZI9yV2hzPATx0UFz8zjVw6lnO4PczdxYhM5zCWQRa/1JNyzfxCZ/LWwJ1J5Fm kxCb+27POcYtNa6GvHpqalqlWHCc1vtQI8PAsM3NCYmEdabrl2OKJDKO9s/V9npNKr7gJjBuPEXBs cAuUlu9ZLyYVZ8WZdvyAXwj8Np66bi5VDruaGDz0puo2Aln75wQSR2iD7aD+M3sof5/tt7v0VDXAk ayFFRFTQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jZCxe-00061v-2k; Thu, 14 May 2020 12:27:38 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id A247C301205; Thu, 14 May 2020 14:27:35 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 9593E213C8B5D; Thu, 14 May 2020 14:27:35 +0200 (CEST) Date: Thu, 14 May 2020 14:27:35 +0200 From: Peter Zijlstra To: Will Deacon Cc: Marco Elver , LKML , Thomas Gleixner , "Paul E. McKenney" , Ingo Molnar , Dmitry Vyukov Subject: Re: [PATCH v5 00/18] Rework READ_ONCE() to improve codegen Message-ID: <20200514122735.GW2978@hirez.programming.kicks-ass.net> References: <20200513111057.GN2957@hirez.programming.kicks-ass.net> <20200513123243.GO2957@hirez.programming.kicks-ass.net> <20200513124021.GB20278@willie-the-truck> <20200513132440.GN2978@hirez.programming.kicks-ass.net> <20200514112142.GV2978@hirez.programming.kicks-ass.net> <20200514120104.GD4280@willie-the-truck> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200514120104.GD4280@willie-the-truck> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 14, 2020 at 01:01:04PM +0100, Will Deacon wrote: > > +#if __has_feature(undefined_sanitizer) > > Hmm, this might want to be __has_feature(undefined_behavior_sanitizer) > (and damn is that hard for a Brit to type out!) (I know right, it should be behaviour, dammit!) I tried without the condition, eg.: +#define __no_sanitize_undefined \ + __attribute__((no_sanitize("undefined"))) and it still generated UBSAN gunk.