From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1ISeXq-0008Fs-KM for qemu-devel@nongnu.org; Tue, 04 Sep 2007 15:58:42 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1ISeXo-0008F5-Sl for qemu-devel@nongnu.org; Tue, 04 Sep 2007 15:58:42 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1ISeXo-0008Ey-Ft for qemu-devel@nongnu.org; Tue, 04 Sep 2007 15:58:40 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29] helo=relay.sgi.com) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1ISeXn-0002vU-Ui for qemu-devel@nongnu.org; Tue, 04 Sep 2007 15:58:40 -0400 Received: from estes.americas.sgi.com (estes.americas.sgi.com [128.162.236.10]) by netops-testserver-4.corp.sgi.com (Postfix) with ESMTP id 7C36061B2C for ; Tue, 4 Sep 2007 12:57:08 -0700 (PDT) Received: from [128.162.232.243] (pc-bjohnson.americas.sgi.com [128.162.232.243]) by estes.americas.sgi.com (Postfix) with ESMTP id EEDC070006E5 for ; Tue, 4 Sep 2007 14:57:07 -0500 (CDT) Message-ID: <46DDB893.2060403@charter.net> Date: Tue, 04 Sep 2007 14:57:07 -0500 From: Brian Johnson MIME-Version: 1.0 References: <1aa37d910709020650v7c491985r761886db64435ac0@mail.gmail.com> <1188852253.10151.3.camel@squirrel> In-Reply-To: <1188852253.10151.3.camel@squirrel> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH] Patches from PyQemu project Reply-To: 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 Anthony Liguori wrote: > On Mon, 2007-09-03 at 18:41 +0300, Blue Swirl wrote: >> Sorry to ruin your GSoC project, but the plugin system was discussed >> last year, please see this thread: >> http://thread.gmane.org/gmane.comp.emulators.qemu/14341/focus=14473 > > I've always agreed that allowing plugins was not a good idea. However, > I had a different thought recently. > > While I don't think there's much of a reason to allow plugins for QEMU, > it would be interesting to make some of QEMU's device emulation into > more a of a library that could be used by other programs. > > With things like KVM making it relatively simple to do CPU emulation, if > QEMU's device emulation was available as a library (even a GPL library), > it would be pretty easy to do interesting things without forking QEMU > which is what everyone seems to be doing these days. Yes -- it would be valuable to have QEMU's devices available as a separate library(ies), with a simple, well-defined API. Some of us use other CPU emulators (yes, yes, I know we should emulate all architectures under qemu, but that's not always easy :) and would love to use qemu's device emulations. > My initial thought is to make the libraries at the individual device > level. It would be good to have a general mechanism for bus providers, interrupts, APICs, chipsets, etc. as well, so we could emulate fancier architectures than a simple PC (or simple Sparc/MIPS/ARM/etc. box.) For instance, I'd like to emulate multiple PCIe host bridges, each with an APIC and multiple cards, which might contain PCI-to-PCI bridges. And I'd like to emulate NUMA systems with many memory controllers and a complex memory map, with multiple sets of chipset registers. I don't expect qemu to do this off the shelf, but I'd like to avoid hardcoding PC assumptions into the device libraries, so I can code the fancy machines myself and use the I/O as-is. Any more thoughts on how to structure the libraries? Brian J. Johnson