From owner-freebsd-hackers@FreeBSD.ORG Sat May 17 08:13:54 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 01ABF1065670 for ; Sat, 17 May 2008 08:13:54 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from hosted.kievnet.com (hosted.kievnet.com [193.138.144.10]) by mx1.freebsd.org (Postfix) with ESMTP id B2F238FC15 for ; Sat, 17 May 2008 08:13:53 +0000 (UTC) (envelope-from avg@icyb.net.ua) Received: from localhost ([127.0.0.1] helo=edge.pp.kiev.ua) by hosted.kievnet.com with esmtpa (Exim 4.62) (envelope-from ) id 1JxHY8-0009G5-Lh for freebsd-hackers@freebsd.org; Sat, 17 May 2008 11:13:52 +0300 Message-ID: <482E93C0.4070802@icyb.net.ua> Date: Sat, 17 May 2008 11:13:52 +0300 From: Andriy Gapon User-Agent: Thunderbird 2.0.0.12 (X11/20080320) MIME-Version: 1.0 To: freebsd-hackers@freebsd.org Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: rdmsr from userspace X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 17 May 2008 08:13:54 -0000 It seems that rdmsr instruction can be executed only at the highest privilege level and thus is not permitted from userland. Maybe we should provide something like Linux /dev/cpu/msr? I don't like interface of that device, I think that ioctl approach would be preferable in this case. Something like create /dev/cpuN and allow some ioctls on it: ioctl(cpu_fd, CPU_RDMSR, arg). What do you think? -- Andriy Gapon