From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932357Ab0FDDER (ORCPT ); Thu, 3 Jun 2010 23:04:17 -0400 Received: from n10-vm0.bullet.mail.in.yahoo.com ([202.86.4.194]:32606 "HELO n10-vm0.bullet.mail.in.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932280Ab0FDDEN convert rfc822-to-8bit (ORCPT ); Thu, 3 Jun 2010 23:04:13 -0400 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 937757.15214.bm@omp105.mail.in2.yahoo.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:X-YMail-OSG:Received:X-Mailer:References:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding; b=gu2fs+q6feBXfGctB0k8vaFD945PaOR3puGNDSPUjXpBoPqjj48v4w/wCjk5YL22uhS2eFrJ8nZ7j1q9CTJ+Cebuc3i3KZE17CEJfV3fnWc+hv4X6cIV1gr8GWxhNW0dbxPJnLrgQxBdClkzbFDOPbjToPhqVrpYn1UH70WvA34=; Message-ID: <831753.25032.qm@web95619.mail.in.yahoo.com> X-YMail-OSG: Iq1LspMVM1kCksXOp7dBZSoYYrEKB6ndSuENj6yzTkKGNCh GZoqsE_916evck.8id7.Lu9BJx6uPJ4E2nvqpwm2qHAv9swPpgLn0uGyvVHh HDx9VMxhMfQHDH7utudYiGtriAFT_36hb7myRtUFzlOYVOKFbZO.YWD8FnON 7s_yTozEcSRvmz.voSdJAKWVKPuXibbs3VyQuVYDkqz_LEPxqPEbnNaz1HjV dxWQmKm86.b0- X-Mailer: YahooMailRC/397.8 YahooMailWebService/0.8.103.269680 References: <324779.32661.qm@web95608.mail.in.yahoo.com> Date: Fri, 4 Jun 2010 08:34:10 +0530 (IST) From: Oza Oza Subject: Re: [PROPOSAL] NMI & register clash handling infrastructure To: linux-kernel@vger.kernel.org In-Reply-To: <324779.32661.qm@web95608.mail.in.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, This is my first post to the group, please excuse me, If I unknowingly miss to follow writing ethics. Proposal/Need: I was working on providing accurate process usage support, and writing a kernel module, I configured cpu-core-unhalted-event and configured LVT (local vector table) with NMI (non-maskable interrupt), and surprisingly Oprofile stopped working, Then I realized, that set_nmi_call back just overwrites nmi_callback function pointer. My proposal/idea/thinking is; have a kernel module which accepts NMI registration from any kernel component, and providing support to the the any kernel service which basically need to service NMI. It may not only supports this, but also can provide central infrastructure which has capabilities such as granting MSR (model specific register) access to the the modules, which may avoid potential clash of MSRs (e.g. two modules are trying to configure same MSR), control NMI registration-unregisteration events etc.. I am not sure, whether this is a good idea or bad idea, but I thought it adds flexibility and some value addition in kernel, and I find this place precisely right to post this idea. Any feedback/suggestions/additions would be appreciated. Regards, Oza. -- 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/