From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Subject: Re: [SeaBIOS] About cpu_set, CPU hotplug and related subjects Date: Wed, 28 Apr 2010 11:31:00 +0200 Message-ID: <4BD80054.9090409@redhat.com> References: <1271705694.2505.36.camel@localhost.localdomain> <20100422011200.GA10677@morn.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Lucas Meneghel Rodrigues , seabios@seabios.org, qemu mailing list , KVM mailing list To: "Kevin O'Connor" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:17208 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751043Ab0D1JbV (ORCPT ); Wed, 28 Apr 2010 05:31:21 -0400 In-Reply-To: <20100422011200.GA10677@morn.localdomain> Sender: kvm-owner@vger.kernel.org List-ID: On 04/22/10 03:12, Kevin O'Connor wrote: > As I understand it, the hotplug support was only in the kvm copy of > bochs bios. It also limited the number of cpus one could use (I think > 16). > > The current smp support in SeaBIOS doesn't limit the number of cpus. > > So, there has been reluctance to just port the old kvm bios code > forward. I believe the number was limited to 15, due to limits in a certain proprietary operating system. The issue with the AML code in BOCHS vs the code in Seabios is a bit tricky. The tables in BOCHS are a fair bit more complicated with the hotplug code and therefore statically generated, whereas Seabios generates them dynamically at boot time. Generating the more complex tables dynamically would be preferred, but it requires like half an AML compiler in Seabios, so it kinda stalled there.... Cheers, Jes