From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH] [RFC] Fix for kvm qemu to return control to gdb stub on breakpoints Date: Thu, 22 May 2008 21:04:03 +0200 Message-ID: <4835C3A3.2010502@web.de> References: <5efefbab7b0f97c983a1.1211473308@thinkpadL> <4835A29C.2090407@web.de> <1211479817.6964.9.camel@thinkpadL> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig64C2EA0F6E2BAF6D8B5663CF" Cc: kvm@vger.kernel.org To: jyoung5@us.ibm.com Return-path: Received: from fmmailgate01.web.de ([217.72.192.221]:36227 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752601AbYEVTEI (ORCPT ); Thu, 22 May 2008 15:04:08 -0400 In-Reply-To: <1211479817.6964.9.camel@thinkpadL> Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig64C2EA0F6E2BAF6D8B5663CF Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Jerone Young wrote: > This is mainly to try and fix the current debug state with using > hardware breakpoints (until your software breakpoint work is ready for Well, you may be lucky with hw-breakpoints on Intel, given userland is patched. But if you aren't (IIRC, current code leaks debug register settings outside the guest, e.g.), I wouldn't invest time here. The debug register handling requires a rewrite in order to support proper virtualization + guest debugging. Right now I'm trying the clean up my debug patches and get things out: 1. Reworked guest debug interface 2. Fixed and enhanced userland support (including soft-BPs) 3. debug register virtualization 4. guest debugging with hw-breakpoints/watchpoints I hope step 1 & 2 can be completed tonight, 3 & 4 finally over the weeken= d. > primetime). I actually do need to submit another patch outside of this > for initialization of some variables (which I see is in your patch too)= , > as it ends up passing down garbage. Yeah, that was another issue. >=20 > For now this is a patch mainly just to get qemu to break into the gdb > stub when a debug interrupt comes in. Though I have a feeling more may > be needed. If you want to fix userland, you also have to ensure that the vcpu thread that received the breakpoint doesn't continue to run - see my patc= h. That said, if you have spare cycles left to spent on the debugging thing, I would try to re-schedule my work and push some packages over to your side. Just let me know! :) Jan --------------enig64C2EA0F6E2BAF6D8B5663CF Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFINcOmniDOoMHTA+kRAvzfAJ9LjaBZCg4z3pYW97U1G5MqMh947wCcCa+P 2khyglWcuqfiXiV+cL9Jz1o= =iFxc -----END PGP SIGNATURE----- --------------enig64C2EA0F6E2BAF6D8B5663CF--