From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anjali Kulkarni Subject: Re: Looking at using KVM for embedded product Date: Wed, 23 Jun 2010 07:57:50 -0700 Message-ID: References: <4C221B21.6060306@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: KVM list To: Anjali Kulkarni Return-path: Received: from exprod7og111.obsmtp.com ([64.18.2.175]:40989 "EHLO exprod7og111.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753036Ab0FWPHM convert rfc822-to-8bit (ORCPT ); Wed, 23 Jun 2010 11:07:12 -0400 In-Reply-To: <4C221B21.6060306@redhat.com> Content-Language: en-US Sender: kvm-owner@vger.kernel.org List-ID: Hi, I am not sure if this is the right forum for my questions - I am using Qemu+KVM on centOS to run my freebsd based virtual OS. The Qemu emulates one of my nics - yukon -II 88E8022 chip. Now, my yukon driver exists in kernel as well as user space(and I will use the one which I want based on some configs). The kernel driver is able to read the bar0 from PCI config and also read contents correctly. The user space driver gets the bar0 correctly, and mmaps it into it's process space, but when it reads contents of bar0, it gets all 0s. This same code when written on a real device works. Is it due to the fact Qemu is running my freebsd based OS in userland, so does mmap require some tweaks? Are there any documents which I could regarding how the Qemu/KVM traps the read write to bar0 so that it can emulate the device reads/writes? If this is not the right forum, can you point me to the right one? Thanks Anjali