From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw01.freescale.net (az33egw01.freescale.net [192.88.158.102]) by ozlabs.org (Postfix) with ESMTP id 9DAFC679F4 for ; Thu, 19 May 2005 02:19:22 +1000 (EST) In-Reply-To: <55497ec3de50301c9f568be24ed3edac@embeddededge.com> References: <55497ec3de50301c9f568be24ed3edac@embeddededge.com> Mime-Version: 1.0 (Apple Message framework v619.2) Content-Type: text/plain; charset=ISO-8859-1; format=flowed Message-Id: <96c735b4d1269864b56c84c72a8a4ac3@freescale.com> From: Kumar Gala Date: Wed, 18 May 2005 11:19:15 -0500 To: "Dan Malek" Cc: linuxppc-embedded@ozlabs.org Subject: Re: [PATCH] ppc32: fix CONFIG_TASK_SIZE handling on 44x List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On May 18, 2005, at 9:14 AM, Dan Malek wrote: > > > On May 18, 2005, at 6:21 AM, Eugene Surovegin wrote: > > > This patch fixed CONFIG_TASK_SIZE handling on 44x. > > Paul suggested to me and I've been contemplating changing > the page table management on PowerPC to something similar > to other platforms.=A0 At first, I was only going to do this on 8xx, > but I think I'll do it for PowerPC in general so all boards can > take advantage if they choose to do so. > > Other ports populate the user page tables with the kernel pmd > entries upon kernel faults, then we don't have to distinguish > among page tables during the TLB exceptions.=A0 I'm hoping we > can populate the init page table entries at boot time, and then > everyone will inherit them, eliminating all faults unless the kernel > vmalloc space grows to need a new pmd entry. I'm a bit concerned about this in the future. On Book-E parts we may=20 end up actually utilizing the address space bit to provide a true 4G/4G=20= split. I understand the current pain in doing this today. I just want=20= you to be aware of what the future might bring. > This would be a generic solution to selecting task size, among > other advanced memory mapping options. > > I'll keep you posted. While we wait on this I think getting Eugene's patch is worth while. - kumar