Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761952AbXK2ROX (ORCPT ); Thu, 29 Nov 2007 12:14:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759497AbXK2ROF (ORCPT ); Thu, 29 Nov 2007 12:14:05 -0500 Received: from wa-out-1112.google.com ([209.85.146.178]:38682 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759877AbXK2ROC (ORCPT ); Thu, 29 Nov 2007 12:14:02 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=D9pg6vDmDN28nQ9b2dOKhSYWb1CbHsGUn3s8nJeODlF1oLx8kqV4cu8PTtJhZqWwIEuZ8QbOxoVRaUpo9+P0dKcFRZ24prq93/lag7bRXZTB9GXQ3PKT6n/Cf6i/gTbKY0d3WvpwADGBQ6L5CNAhPxKtF0JCkR5LxfzoH/hNeIA= Message-ID: <3ae72650711290914q162e81a8l9fbecf1a1196ba79@mail.gmail.com> Date: Thu, 29 Nov 2007 18:14:02 +0100 From: "Kay Sievers" To: "Robert P. J. Day" Subject: Re: does /proc/sys/kernel/modprobe actually do anything? Cc: "Alexey Dobriyan" , linux-kernel@vger.kernel.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: X-Google-Sender-Auth: 9abb5e0f243e8e3e Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1908 Lines: 42 On Nov 29, 2007 1:58 PM, Robert P. J. Day wrote: > On Thu, 29 Nov 2007, Alexey Dobriyan wrote: > > > On 11/29/07, Robert P. J. Day wrote: > > > echo '#! /bin/sh' > /tmp/modprobe > > > echo 'echo "$@" >> /tmp/modprobe.log' >> /tmp/modprobe > > > echo 'exec /sbin/modprobe "$@"' >> /tmp/modprobe > > > chmod a+x /tmp/modprobe > > > echo /tmp/modprobe > /proc/sys/kernel/modprobe > > > > > > i've tried that and i don't see that it does anything whatsoever. i > > > ran modprobe under "strace" and it doesn't appear to make any effort > > > to check /proc/sys/kernel/modprobe. > > > > Kernel, not modprobe, checks /proc/sys/kernel/modprobe . > > actually, ignore that earlier query of mine, i've found the relevant > code under kernel/ in sysctl.c and sysctl_check.c and kmod.c. but > it's still not clear why what is described in > Documentation/debugging-modules.txt (and shown above) doesn't work, so > i'm still open to suggestions. thanks. Kernel code can request a module to be loaded by calling request_module(). The /proc/sys/kernel/modprobe value is the path to the binary which the kernel executes when this function is called. It is used by some modules, or if you open an existing device node which has no actual driver loaded. Most modules are loaded by device id's (modalias) of a device. The module is loaded by pure userspace tools and not by the kernel and therefore /proc/sys/kernel/modprobe is not involved at all in most module loading. The text in Documentation/debugging-modules.txt is purely about kernel module loading requests, and not helpful for the common module loading case. Kay - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/