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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT autolearn=ham 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 45286C433F4 for ; Thu, 30 Aug 2018 10:39:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E4F9E2073D for ; Thu, 30 Aug 2018 10:39:10 +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="K851uWF5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E4F9E2073D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728439AbeH3Oki (ORCPT ); Thu, 30 Aug 2018 10:40:38 -0400 Received: from merlin.infradead.org ([205.233.59.134]:33348 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728311AbeH3Okh (ORCPT ); Thu, 30 Aug 2018 10:40:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.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=7vglJ+NZ4ZmZvWkw+w6q7eF3N8xslbTy/DARKonGKgo=; b=K851uWF5RgWAbj/vPmWA8yYRS MLqzj+iDYTxLYKegi6vyUn74FiNbsLvUp1V58+icaBCCokHTf3jq33o4o22/ubezCPksTu9CLJE/h zFeb+PEpM0DJd25TLKqc+mc82+1zOoPy3ZnyVlrwenR4GSTH4A0cNdwe0lkR6U8m9lOMaiUWPrQux ws9jQuj9lEgABcrxQx7/Lad4pDoHqtbifqZWI3xbbUMTHqY0+XIRs7aVGkZkLJlD0iicMm1tcic8w siCZWE0A3vIPBNS9nltbLKz1BQQVkUjzRrRTtZbzM1crqYP30BVzBGv9TTEtZfjIZMkN7wdB0EUh2 WT2yyAv5w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fvKLx-00085r-RK; Thu, 30 Aug 2018 10:39:06 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 877042024EB08; Thu, 30 Aug 2018 12:39:04 +0200 (CEST) Date: Thu, 30 Aug 2018 12:39:04 +0200 From: Peter Zijlstra To: Rich Felker Cc: Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: futex_cmpxchg_enabled breakage Message-ID: <20180830103904.GA24160@hirez.programming.kicks-ass.net> References: <20180829222221.GA22017@brightrain.aerifal.cx> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180829222221.GA22017@brightrain.aerifal.cx> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 29, 2018 at 06:22:21PM -0400, Rich Felker wrote: > If there are archs that support SMP but don't provide their own Then throw it out the window and drive over it with a tank. Seriously, an SMP architecture that doesn't have native cmpxchg (or equivalent) is not worth anybodies time.