From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Harper <james.harper@bendigoit.com.au>
Subject: RE: [Xen-devel] Fwd: NetBSD xl core-dump not working... Memory
 fault (core dumped)
Date: Tue, 10 Dec 2013 09:27:17 +0000
Message-ID: <6035A0D088A63A46850C3988ED045A4B66BFFC48@BITCOM1.int.sbss.com.au>
References: <52770EED.9090804@gmx.de> <52781C27.2040508@gmail.com>
	<1383820189.26213.152.camel@kazak.uk.xensource.com>
	<b122ef56-f161-4b70-9a2a-aa7a467d741a@email.android.com>
	<1383906558.3189.81.camel@kazak.uk.xensource.com>
	<5281F953.2060101@citrix.com>
	<1384250453.1883.37.camel@kazak.uk.xensource.com>
	<5281FE63.2060503@citrix.com>
	<e491eeb7-4576-4a0b-9ade-4b8504632b71@email.android.com>
	<5283730B.2020900@citrix.com> <529E1F9F.5040501@gmail.com>
 <6035A0D088A63A46850C3988ED045A4B66BFFA30@BITCOM1.int.sbss.com.au>
Mime-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Return-path: <bounces-port-xen-owner-gonpx-port-xen=m.gmane.org@NetBSD.org>
In-Reply-To: <6035A0D088A63A46850C3988ED045A4B66BFFA30@BITCOM1.int.sbss.com.au>
Content-Language: en-US
Sender: port-xen-owner@NetBSD.org
To: James Harper <james.harper@bendigoit.com.au>, "Mike C." <miguelmclara@gmail.com>, =?iso-8859-1?Q?Roger_Pau_Monn=E9?= <roger.pau@citrix.com>, Ian Campbell <Ian.Campbell@citrix.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, "port-xen@netbsd.org" <port-xen@netbsd.org>
List-Id: xen-devel@lists.xenproject.org

>=20
> I've been working with Mike on this today. After he re-applied the patch
> (something must have gone wrong initially), an ioctl error is repeated
> constantly instead of SIGSEGV:
>=20
> xc: error: xc_map_foreign_range: ioctl failed (14 =3D Bad address): Inter=
nal
> error
>=20
> I dumped out some of the variables though, and:
>=20
> nr_memory_map =3D 1
> pfn_start =3D 0, pfn_end =3D 1048575
>=20
> this equates to 4GB of pfn's to be dumped on a vm with mem/maxmem =3D
> 256MB... is there code that skips empty pages? If not, that seems to be t=
he
> explanation for the errors.
>=20

A bit more info with a bit more debugging printf's, and removing the perror=
 in xc_map_foreign_range:

nr_pages =3D 64472
nr_memory_map =3D 1
map_idx =3D 0
 pfn_start =3D 0, pfn_end =3D 1048575
xc: info: j (63456) !=3D nr_pages (64472)

The resulting dump file is readable by my xen->windows dump converter, and =
the windows debugger doesn't complain about the resulting windows dump file=
, so it seems to be working okay.

James