From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFC][PATCH 01/11] asm-generic/tlb: Provide a comment Date: Thu, 13 Sep 2018 14:39:37 +0200 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 Return-path: Content-Disposition: inline In-Reply-To: <20180913141827.1776985e@mschwideX1> Sender: linux-kernel-owner@vger.kernel.org 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 List-Id: linux-arch.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. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 Date: Thu, 13 Sep 2018 14:39:37 +0200 From: Peter Zijlstra 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> Sender: linux-arch-owner@vger.kernel.org List-ID: 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 Message-ID: <20180913123937.F0Mh_31jDSps0q8gZdnb5fKSVy0xGZ5d_wtN1FSK_ug@z> 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.