From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932256AbWF0LwF (ORCPT ); Tue, 27 Jun 2006 07:52:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932482AbWF0LwE (ORCPT ); Tue, 27 Jun 2006 07:52:04 -0400 Received: from e4.ny.us.ibm.com ([32.97.182.144]:12196 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S932256AbWF0LwD (ORCPT ); Tue, 27 Jun 2006 07:52:03 -0400 Subject: [RFC][PATCH 0/3] Process events biarch bug: Intro From: Matt Helsley To: LKML Cc: Evgeniy Polyakov , Guillaume Thouvenin Content-Type: text/plain Date: Tue, 27 Jun 2006 04:47:01 -0700 Message-Id: <1151408822.21787.1807.camel@stark> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org The events sent by Process Events from a 64-bit kernel are not binary compatible with what a 32-bit userspace program would expect to recieve because the timespec struct (used to send a timestamp) is not the same. This means that fields stored after the timestamp are offset and programs that don't take this into account break under these circumstances. This is a problem for 32-bit userspace programs running with 64-bit kernels on ppc64, s390, x86-64.. any "biarch" system. This series: 1 - Gives a name to the union of the process events structure so it may be used to work around the problem from userspace. 2 - Comments on the bug and describes a userspace workaround in Documentation/connector/process_events.txt 3 - Implements a second connector interface without the problem (Removing the old interface or changing the definition would break binary compatibility) Compiled, booted, and lightly tested. Comments or suggestions on alternate approaches would be appreciated. Cheers, -Matt Helsley