From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: Re: [patch]Add a new reboot method Date: Thu, 29 May 2008 17:01:15 +0100 Message-ID: <20080529170115.4fe39d72@core> References: <20080529155926.17dffcf6@core> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: Huacai Chen , xen-devel@lists.xensource.com, Jan Beulich List-Id: xen-devel@lists.xenproject.org On Thu, 29 May 2008 16:49:46 +0100 Keir Fraser wrote: > On 29/5/08 15:59, "Alan Cox" wrote: > > >> ACPI *can* be involved in rebooting though, via FADT's RESET_REGISTER. > >> Question is: why does Linux ignore this reboot method? > > > > It doesn't. Well at the least upstream version doesn't. We default to > > keyboard currently but that probably wants reconsidering for modern > > systems. > > Well, I have to disagree. Looks to me like ACPI reboot is supposed to be > implemented by acpi_reboot() and looking at 2.6.26-rc4 that function is > still stubbed out. Am I missing something? My fault. I was looking in the tree I run not the upstream tree. We've had patches available for it since mid 2007. Looks like they got stuck somewhere around Andi Kleen. The original thread seems to be this one: http://linux.derkeiler.com/Mailing-Lists/Kernel/2007-07/msg06145.html although it doesn't appear to check the fadt hdr rev is > 1 now I look harder. Looks easy enough to try in Xen, and perhaps that would also meet Huacai's needs ? Alan