From owner-freebsd-current@FreeBSD.ORG Wed Dec 2 22:48:02 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C97211065672 for ; Wed, 2 Dec 2009 22:48:02 +0000 (UTC) (envelope-from kevin@your.org) Received: from mail.your.org (chi02.mail.your.org [204.9.55.23]) by mx1.freebsd.org (Postfix) with ESMTP id 97C4A8FC08 for ; Wed, 2 Dec 2009 22:48:02 +0000 (UTC) Received: from mail.your.org (chi02.mail.your.org [204.9.55.23]) by mail.your.org (Postfix) with ESMTP id E69BC18068BB; Wed, 2 Dec 2009 22:48:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=your.org; h=subject :mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; s=selector1 ; bh=pnPYaWYNZBdQ5mgkW3rwCCqpo0M=; b=QannEjtWLOAEyDmOsXsnfMU+rad VFatZRGqgDKrzWJaqVpXVhwenX79npS1XpTBZFFoGtVCzTEl5/zwr36o+JhLNeoX wqhSjhyC0Xzx4EUCX0sDB+pJgB6/lqFMbvmGh4F7w+ml4zgFIfz1HVSe/2R0DVEN McqYqP0NHTjocj6g= DomainKey-Signature: a=rsa-sha1; c=nofws; d=your.org; h=subject:mime-version :content-type:from:in-reply-to:date:cc:content-transfer-encoding :message-id:references:to; q=dns; s=selector1; b=F38gYR9/JmwhPJX v+yR3rB/I/7UXoCNvorHagVPxrdwsmCfEr33V9QsZD7njQo9iWc2z4mR+VcBuFaT zJ4l6eNkCDWk7UX1I4473rWlev3/jZiopt1ccOLFOvDfibXT6DZAVTjew3PtGQ4+ J20vJ2f7KFfQM9ssEmpkuip4G+sQ= Received: from vpn177.ord02.your.org (vpn177.ord02.your.org [204.9.55.177]) by mail.your.org (Postfix) with ESMTPA id 9885918068BA; Wed, 2 Dec 2009 22:48:01 +0000 (UTC) Mime-Version: 1.0 (Apple Message framework v1076) Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes From: Kevin In-Reply-To: Date: Wed, 2 Dec 2009 16:48:00 -0600 Content-Transfer-Encoding: 7bit Message-Id: References: <3EA83F9F-BE44-4C64-852F-CDC09FB63B94@your.org> To: Kevin X-Mailer: Apple Mail (2.1076) Cc: freebsd-current@freebsd.org Subject: Re: 8.0 still doesn't boot in Xen (kern/138863) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 02 Dec 2009 22:48:02 -0000 On Nov 24, 2009, at 12:00 PM, Kevin wrote: > > On Nov 24, 2009, at 11:20 AM, Kevin wrote: > >> >> Is it too late in the 8.0 release schedule to look at kern/138863? >> Between 7.x and 8.0 the kernel can no longer boot under Xen due to >> changes involving CLFLUSH. The effect is a crash very early in the >> boot, with no workaround. (This is under Xen's fully virtualized >> mode, not the XEN platform port underway.) >> >> This was also mentioned on the Xen mailing lists back in September (http://lists.freebsd.org/pipermail/freebsd-xen/2009-September/000310.html >> ) but nothing has been committed to fix this yet. >> >> XenServer is getting pretty popular in some enterprise and hosting >> environments, so having 8.0 not bootable would be a bit >> disappointing. :) > > I was just pointed to the change from a couple of days ago, adding > the tunable "hw.clflush_disable". This looks like it might do what I > need, so I'm building a new bootable CD to find out and update the PR. > > This should probably be documented somewhere, just so someone in a > similar situation even knows about this tunable. > > -- Kevin Just to follow up, 8.0-RELEASE still doesn't boot for me on XenServer 5.5.0 on an AMD CPU. Without setting hw.clflush_disable, I get the same panic as before mentioned in the PR. If I do set clflush_disable, I get an endless stream of Trap 12 messages, giving instruction pointers all over the place. The last time 8.0 was bootable was in the -BETA timeframe. Does anyone have any other suggestions on where to look? It still works fine on the same software using an Intel CPU, so somehow that's significant. -- Kevin