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 B52A4C04ABB for ; Thu, 13 Sep 2018 12:39:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55D1B20861 for ; Thu, 13 Sep 2018 12:39:59 +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="ZpZhNMsR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 55D1B20861 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 S1727127AbeIMRtO (ORCPT ); Thu, 13 Sep 2018 13:49:14 -0400 Received: from merlin.infradead.org ([205.233.59.134]:56832 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726819AbeIMRtO (ORCPT ); Thu, 13 Sep 2018 13:49:14 -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=gmScunkOuJMb6n5DsV3A7MCcYH8oPFce7O8It6FRQ0U=; b=ZpZhNMsRuxSgB0GNtu3GzAWXb sGsL5ZpQD3VHPKzN+YSpIUZAUUBYaT62kbSlVXYGP0OQOi/LqlyWsKCPdS+ljOhqf20HpZzD9WBou w91nqjEU3wwrAElGyWpplWcMv/CJIpn72tfhJWPJOI4jDd25ZyBtr7PRA9eLYwr5tZHLMDHvJo7HL DMBjKOvJPh2JjTuZF64khadIyFnEYQjT7RuNc5Z7RD248lOMQ/vTCfCPNxMBLgtNZIpzb17i99hZ1 ZXbmvvROFnBIuPFG9bAcboRQ/93bVulBtfBIXNrvhvILDShjXHmqXL3kV6fxUpNIzNuAkbnZITrBD wuPpXfHew==; 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 1g0QuJ-0002fk-Qf; Thu, 13 Sep 2018 12:39:40 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 344BE202C1A2D; Thu, 13 Sep 2018 14:39:37 +0200 (CEST) Date: Thu, 13 Sep 2018 14:39:37 +0200 From: Peter Zijlstra To: Martin Schwidefsky Cc: will.deacon@arm.com, aneesh.kumar@linux.vnet.ibm.com, akpm@linux-foundation.org, npiggin@gmail.com, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux@armlinux.org.uk, heiko.carstens@de.ibm.com Subject: Re: [RFC][PATCH 01/11] asm-generic/tlb: Provide a comment Message-ID: <20180913123937.GX24124@hirez.programming.kicks-ass.net> References: <20180913092110.817204997@infradead.org> <20180913092811.894806629@infradead.org> <20180913123014.0d9321b8@mschwideX1> <20180913105738.GW24124@hirez.programming.kicks-ass.net> <20180913141827.1776985e@mschwideX1> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180913141827.1776985e@mschwideX1> 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 Thu, Sep 13, 2018 at 02:18:27PM +0200, Martin Schwidefsky wrote: > We may get something working with a common code mmu_gather, but I fear the > day someone makes a "minor" change to that subtly break s390. The debugging of > TLB related problems is just horrible.. Yes it is, not just on s390 :/ And this is not something that's easy to write sanity checks for either AFAIK. I mean we can do a few multi-threaded mmap()/mprotect()/munmap() proglets and catch faults, but that doesn't even get close to covering all the 'fun' spots. Then again, you're more than welcome to the new: MMU GATHER AND TLB INVALIDATION section in MAINTAINERS.