From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH 2/5] KVM: New guest debug interface Date: Mon, 08 Dec 2008 10:42:34 +0100 Message-ID: <493CEC0A.7000505@siemens.com> References: <20081127114342.10901.31992.stgit@mchn012c.ww002.siemens.net> <20081127114343.10901.26107.stgit@mchn012c.ww002.siemens.net> <493B9DAE.7050007@redhat.com> <493CE546.2030507@siemens.com> <493CEA10.2000104@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, Hollis Blanchard , Joerg Roedel To: Avi Kivity Return-path: Received: from lizzard.sbs.de ([194.138.37.39]:15305 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751305AbYLHJnH (ORCPT ); Mon, 8 Dec 2008 04:43:07 -0500 In-Reply-To: <493CEA10.2000104@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity wrote: > Jan Kiszka wrote: >>>> Note that both SVM and VTX are supported, but only the latter was >>>> tested >>>> yet. Based on the experience with all those VTX corner case, I would be >>>> fairly surprised if SVM will work out of the box. >>>> >>>> >>> I'd like svm to work before applying. >>> >> >> To validate the design? >> >> > > To make sure it doesn't oops, and to make sure it works. > >> I will see if I can organize an SVM box, but I can't promise when I'll >> be able to do the testing. Anyone willing to contribute time on this >> would be warmly welcome! >> >> > > I happen to have an svm box. How do you test this? play with gdb inside > and outside the guest? For inside the box, I also use the kgdb testsuite (kgbts). For guest debugging check, some manual interaction is required: Set a breakpoint on a prominent symbol (my favorite is sys_execve), do some single stepping, check that smp works (breakpoint hits on all vcpus), add some watchpoint and check if it triggers at reasonable spots (I recently did a short demo with first trapping hrtimer_start, grabbing &timer->state and then set a watchpoint on that address to catch changes). > > You could also try qemu's svm emulation, but it may be a little slow, > and probably hasn't been well tested in these areas. > Yeah, could be a supplemental test. Jan -- Siemens AG, Corporate Technology, CT SE 26 Corporate Competence Center Embedded Linux