From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mtagate6.de.ibm.com ([195.212.29.155]:26428 "EHLO mtagate6.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753568AbXKORNJ (ORCPT ); Thu, 15 Nov 2007 12:13:09 -0500 Subject: Re: [patch 3/3] arch_rebalance_pgtables call From: Martin Schwidefsky Reply-To: schwidefsky@de.ibm.com In-Reply-To: <1195078053.28865.47.camel@pasglop> References: <20071112143009.425807965@de.ibm.com> <20071112144010.052155135@de.ibm.com> <200711132333.38086.nickpiggin@yahoo.com.au> <1195032394.9446.6.camel@localhost> <1195034796.28865.36.camel@pasglop> <1195040986.9446.23.camel@localhost> <1195078053.28865.47.camel@pasglop> Content-Type: text/plain Date: Thu, 15 Nov 2007 18:13:06 +0100 Message-Id: <1195146786.21505.4.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org To: benh@kernel.crashing.org Cc: Nick Piggin , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org List-ID: On Thu, 2007-11-15 at 09:07 +1100, Benjamin Herrenschmidt wrote: > On Wed, 2007-11-14 at 12:49 +0100, Martin Schwidefsky wrote: > > > > They all either have an arch override, call get_unmapped_area again or > > are not relevant. So it should be possible to do the upgrade in > > arch_get_unmapped_area. I still have my doubts though, all future uses > > of the get_unmapped_area pointer have to be checked and I feel it is > > easier to understand to do the upgrade / rebalance of the page table > > at > > the end of get_unmapped_area where every caller of mmap is guaranteed > > to > > pass through. > > Well, if something does what you are worried about, then it would be > broken on powerpc as well (among others). We have various constraints on > the address space layout that must be handled by our arch g_u_a (or our > hugetlb one). Ok, I rearranged the dynamic page tables code (and fixed the bug that 31 bit processes had a 3 level page table instead of 2). It is working fine with s390 specific versions of arch_get_unmapped_area and arch_get_unmapped_area_topdown which do the page table upgrade. Which means we can drop the arch_rebalance_pgtables-call.patch from -mm again. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin.