From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: Issue: qemu-kvm with gdb Date: Thu, 24 Mar 2011 08:14:36 +0100 Message-ID: <4D8AEF5C.6000207@web.de> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig2E318D5A5E468A88DF7729A5" Cc: kvm@vger.kernel.org To: shiv chauhan Return-path: Received: from fmmailgate02.web.de ([217.72.192.227]:37538 "EHLO fmmailgate02.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933034Ab1CXHOi (ORCPT ); Thu, 24 Mar 2011 03:14:38 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig2E318D5A5E468A88DF7729A5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 2011-03-24 07:17, shiv chauhan wrote: > Hi all, >=20 > While remote debugging a kernel (not written in C and no debugging > symbols) using qemu-kvm with gdb, strange it does not stop at > breakpoint though qemu works well: >=20 > Commands: > # qemu-kvm -s -S -hda hd.img & > #gdb > (gdb) target remote localhost:1234 > Remote debugging using localhost:1234 > 0x0000fff0 in ?? () > (gdb) break *0x200020 > Breakpoint 1 at 0x200020 > (gdb) c >=20 > This break point never reach, though I am sure this address comes in > execution control path, above all same sequence of commands work well > with qemu, anybody else faced such issue? or any explanation for this > behavior? Breakpoints in emulation mode are like hardware breakpoints: It doesn't matter if the guest writes to their location. However, KVM software breakpoints (the default) work via injecting an INT3 into the guest code. So you may be more lucky with hbreak. Jan --------------enig2E318D5A5E468A88DF7729A5 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk2K71wACgkQitSsb3rl5xQEZgCgs0lbC80Jm0br06lqbdK0QuaK KpQAoOXxMS3pq+vnTj5z9J8/BweI10Rn =oiB4 -----END PGP SIGNATURE----- --------------enig2E318D5A5E468A88DF7729A5--