From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755695AbWKQLb1 (ORCPT ); Fri, 17 Nov 2006 06:31:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933531AbWKQLb1 (ORCPT ); Fri, 17 Nov 2006 06:31:27 -0500 Received: from web23112.mail.ird.yahoo.com ([217.146.189.52]:46716 "HELO web23112.mail.ird.yahoo.com") by vger.kernel.org with SMTP id S1755695AbWKQLb0 convert rfc822-to-8bit (ORCPT ); Fri, 17 Nov 2006 06:31:26 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.fr; h=Message-ID:Received:Date:From:Subject:To:MIME-Version:Content-Type:Content-Transfer-Encoding; b=3EDllOeHbantNNHA5x4njZ1EI95tAp5nGaaEzTdkp0MOd0MjMZS38lhTmxLpIdIbOFzdaub7U49GPoohbmJXlxsfmcmrrQLx0ca2FbXto4qLqKTdYlrzc4RSC3f3hr+RHO5g4wgVqztqqgyrEKKQqis7xQpOB8TQM39xUghLk3c= ; Message-ID: <20061117113124.75132.qmail@web23112.mail.ird.yahoo.com> Date: Fri, 17 Nov 2006 11:31:24 +0000 (GMT) From: moreau francis Subject: vm: weird behaviour when munmapping To: linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hmm, I'm probably missing something but I don't see what. Please be nice even if the question is really stupid ;) I'm looking at mmap.c code and to understand it I decided to implement a dumb char device that implement its own foo_mmap() method. In this method it defined its own vma ops: static void foo_vma_open(struct vm_area_struct *vma) static void foo_vma_close(struct vm_area_struct *vma) A dumb application mmap the device in order to make foo_mmap() install the vma ops. mmap(NULL, 16384, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); mmap returned 0x2aaae000 for example. Until now, foo_vma_open() and foo_vma_close() are not called. Now I want to unmap the first part of the previous mapping to see how vma ops are called. So I did: munmap(0x2aaae000, 1024); and here's what happen: foo_vma_open(vma) is called with: vma->vm_start = 0x2aaae000 vma->vm_end = 0x2aaaf000 foo_vma_close(vma) is called with: vma->vm_start = 0x2aaae000 vma->vm_end = 0x2aaaf000 However I would have expected: foo_vma_open(vma) is called with: vma->vm_start = 0x2aaaf000 vma->vm_end = 0x2aaab2000 foo_vma_close(vma) is called with: vma->vm_start = 0x2aaae000 vma->vm_end = 0x2aaaf000 Can anybody tell me why I get this behaviour ? thanks Francis ___________________________________________________________________________ Découvrez une nouvelle façon d'obtenir des réponses à toutes vos questions ! Profitez des connaissances, des opinions et des expériences des internautes sur Yahoo! Questions/Réponses http://fr.answers.yahoo.com