From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 10 Sep 2002 09:29:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 10 Sep 2002 09:29:05 -0400 Received: from quark.didntduck.org ([216.43.55.190]:27917 "EHLO quark.didntduck.org") by vger.kernel.org with ESMTP id ; Tue, 10 Sep 2002 09:29:04 -0400 Message-ID: <3D7DF4B1.6010300@didntduck.org> Date: Tue, 10 Sep 2002 09:33:37 -0400 From: Brian Gerst User-Agent: Mozilla/5.0 (Windows; U; WinNT4.0; en-US; rv:1.1) Gecko/20020826 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Venu Vadapalli CC: linux-kernel@vger.kernel.org Subject: Re: vmalloc/vfree References: <3D81FB0C@zathras> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Venu Vadapalli wrote: > Looking at vmalloc implementation, it fills the page table mappings (pgd and > pmd) of only init_mm. When other tasks access these pages their mappings are > updated on demand by the page fault handler, right? Vfree, also, updates the > entries of just init_mm and, of course, flushes the cache and the tlb. But > what about other tasks that have acquired mappings to these pages? > > -Venu The pagetables for the kernel space are shared between all processes, except for the top level which is why the page fault handler exists. The actual pages that make up the shared pagetables never change once allocated which is the reason we can be lazy about updating the top level table of each task. -- Brian Gerst