From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1CsMou-00036V-2C for qemu-devel@nongnu.org; Sat, 22 Jan 2005 10:05:00 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1CsMlQ-0002WF-46 for qemu-devel@nongnu.org; Sat, 22 Jan 2005 10:01:27 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1CsMlM-0002Pl-6a for qemu-devel@nongnu.org; Sat, 22 Jan 2005 10:01:20 -0500 Received: from [64.233.184.204] (helo=wproxy.gmail.com) by monty-python.gnu.org with esmtp (Exim 4.34) id 1CsMGS-0005YR-OH for qemu-devel@nongnu.org; Sat, 22 Jan 2005 09:29:24 -0500 Received: by wproxy.gmail.com with SMTP id 68so290807wri for ; Sat, 22 Jan 2005 06:29:24 -0800 (PST) Message-ID: Date: Sat, 22 Jan 2005 09:29:24 -0500 From: Karl Magdsick Subject: Re: [Qemu-devel] OT: Running qemu without host os? In-Reply-To: <20050122040545.GA4374@jbrown.mylinuxbox.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit References: <20050121170202.GA11609@jbrown.mylinuxbox.org> <20050121192314.GA12367@jbrown.mylinuxbox.org> <20050122040545.GA4374@jbrown.mylinuxbox.org> Reply-To: Karl Magdsick , qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org > > If you had qemu running multiple OSes, and all of them could access the same > hardware "virtually directly", that would be simply amazing. Not quite sure > how one could go about doing this though.. > Unless all of the guest OSes were modified to be aware that they were sharing hardware (or else some really intelligent dynamic patching was going on), the OSes would step all over eachother. For instance, one guest OS might put the NIC in promiscuous mode right before another guest OS boots and re-initializes the NIC to non-promiscuous mode. A third guest OS might then change the MAC address on the NIC and screw up ARP. However, your idea isn't that much different from the (fairly new) exokernel concept, where each process has its own copy of virtualized hardware, with simulated direct access from userspace, and each process has its own drivers. My understanding is that the drivers would usually be implemented as dynamic libraries, so most of the applications would actually be sharing driver implementations. -Karl