From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: guest hardware breakpoint Date: Fri, 31 Oct 2008 11:11:26 +0100 Message-ID: <490AD9CE.9030705@siemens.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Michael Le Return-path: Received: from lizzard.sbs.de ([194.138.37.39]:20449 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750741AbYJaKLe (ORCPT ); Fri, 31 Oct 2008 06:11:34 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: Michael Le wrote: > Hi, > > I'm trying to set a hardware breakpoint inside the guest using gdb. This > doesn't seem to work. Execution just skips right over it. I've have also > tried writing some code to set a breakpoint by directly accessing the db > registers from the guest. This also did not cause a breakpoint to be > generated in the guest. Is it possible to use hardware breakpoints > inside the guest? Is there some configuration that must be set in qemu > or in the kvm modules? > > The guest vm is running linux 2.6.18. > > I'm using kvm-77 with linux kernel 2.6.27. I used the kvm kernel modules > that came with the linux kernel and not from kvm-77. I have an x86 > machine. The command I use to run the vm is the following: > > ../kvm/qemu-system-x86_64 main.img -m 512 -vnc :0 For now you need these patch queues for hw breakpoint support: http://thread.gmane.org/gmane.comp.emulators.kvm.devel/22838 http://thread.gmane.org/gmane.comp.emulators.kvm.devel/22818 Dunno if they applied to -77, but I can provide rebases against latest git on request. Jan -- Siemens AG, Corporate Technology, CT SE 2 Corporate Competence Center Embedded Linux