From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:42944)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <rjones@redhat.com>) id 1UeMbC-0005G5-Tv
	for qemu-devel@nongnu.org; Mon, 20 May 2013 05:41:48 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <rjones@redhat.com>) id 1UeMbB-00011g-DG
	for qemu-devel@nongnu.org; Mon, 20 May 2013 05:41:46 -0400
Received: from mx1.redhat.com ([209.132.183.28]:64270)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <rjones@redhat.com>) id 1UeMbB-00011T-5i
	for qemu-devel@nongnu.org; Mon, 20 May 2013 05:41:45 -0400
Received: from int-mx02.intmail.prod.int.phx2.redhat.com
	(int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12])
	by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r4K8oFb3007835
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK)
	for <qemu-devel@nongnu.org>; Mon, 20 May 2013 04:50:15 -0400
Date: Mon, 20 May 2013 09:49:59 +0100
From: "Richard W.M. Jones" <rjones@redhat.com>
Message-ID: <20130520084959.GA20976@redhat.com>
References: <1369033424-14594-1-git-send-email-famz@redhat.com>
	<20130520084106.GC18311@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <20130520084106.GC18311@redhat.com>
Content-Transfer-Encoding: quoted-printable
Subject: Re: [Qemu-devel] [PATCH v3 00/10] curl: fix curl read
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Fam Zheng <famz@redhat.com>
Cc: kwolf@redhat.com, jcody@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com

On Mon, May 20, 2013 at 09:41:06AM +0100, Richard W.M. Jones wrote:
> On Mon, May 20, 2013 at 03:03:34PM +0800, Fam Zheng wrote:
> > CURL library API has changed, the current curl driver is not working.
> > This patch rewrites the use of API as well as the structure of intern=
al
> > states.=20
>=20
> I tried this, but it segfaults:
>=20
> Program terminated with signal 11, Segmentation fault.

That stack trace was wrong.  I was testing against the version of
libcurl in Fedora which is known to be broken.

Here is the stack trace, this time really running against
curl-7_30_0-147-gae26ee3:

Program terminated with signal 11, Segmentation fault.
#0  curl_read_cb (ptr=3D<optimized out>, size=3D<optimized out>,=20
    nmemb=3D<optimized out>, opaque=3D0x7f63d48ba340) at block/curl.c:240
240         size_t aio_base =3D acb->sector_num * SECTOR_SIZE;
Missing separate debuginfos, use: debuginfo-install SDL-1.2.15-3.fc18.x86=
_64 bluez-libs-4.101-6.fc18.x86_64 brlapi-0.5.6-12.fc18.x86_64 celt051-0.=
5.1.3-5.fc18.x86_64 ceph-devel-0.56.3-1.fc18.x86_64 ceph-libs-0.56.3-1.fc=
18.x86_64 cryptopp-5.6.2-2.fc18.x86_64 cyrus-sasl-lib-2.1.25-2.fc18.x86_6=
4 leveldb-1.7.0-4.fc18.x86_64 libfdt-1.3.0-5.fc18.x86_64 libseccomp-1.0.1=
-0.fc18.x86_64 libselinux-2.1.12-7.3.fc18.x86_64 libusbx-1.0.14-1.fc18.x8=
6_64 nss-mdns-0.10-11.fc18.x86_64 snappy-1.0.5-2.fc18.x86_64 spice-server=
-0.12.2-3.fc18.x86_64 usbredir-0.6-1.fc18.x86_64 xen-libs-4.2.2-3.fc18.x8=
6_64
(gdb) bt
#0  curl_read_cb (ptr=3D<optimized out>, size=3D<optimized out>,=20
    nmemb=3D<optimized out>, opaque=3D0x7f63d48ba340) at block/curl.c:240
#1  0x00007f63cef51cc8 in Curl_client_write ()
   from /home/rjones/d/curl/lib/.libs/libcurl.so.4
#2  0x00007f63cef697ef in Curl_readwrite ()
   from /home/rjones/d/curl/lib/.libs/libcurl.so.4
#3  0x00007f63cef710b0 in multi_runsingle ()
   from /home/rjones/d/curl/lib/.libs/libcurl.so.4
#4  0x00007f63cef720f7 in multi_socket ()
   from /home/rjones/d/curl/lib/.libs/libcurl.so.4
#5  0x00007f63cef721df in curl_multi_socket_action ()
   from /home/rjones/d/curl/lib/.libs/libcurl.so.4
#6  0x00007f63d27d9043 in curl_fd_handler (arg=3D0x7f63d48e16c0)
    at block/curl.c:265
#7  0x00007f63d27bcbbb in aio_dispatch (ctx=3D0x7f63d48b33f0, ctx=3D0x7f6=
3d48b33f0)
    at aio-posix.c:149
#8  0x00007f63d27bd0b1 in aio_poll (ctx=3D0x7f63d48b33f0,=20
    blocking=3Dblocking@entry=3Dtrue) at aio-posix.c:248
#9  0x00007f63d29019c9 in qemu_aio_wait () at main-loop.c:484
#10 0x00007f63d27d2b65 in bdrv_rwv_co (bs=3Dbs@entry=3D0x7f63d48b96e0,=20
    sector_num=3Dsector_num@entry=3D0, qiov=3Dqiov@entry=3D0x7fff2c127e10=
,=20
    is_write=3Dis_write@entry=3Dfalse) at block.c:2215
#11 0x00007f63d27d2c90 in bdrv_rw_co (is_write=3Dfalse,=20
    nb_sectors=3D<optimized out>, buf=3D<optimized out>, sector_num=3D0, =
bs=3D
    0x7f63d48b96e0) at block.c:2234
#12 bdrv_read (bs=3Dbs@entry=3D0x7f63d48b96e0, sector_num=3Dsector_num@en=
try=3D0,=20
    buf=3Dbuf@entry=3D0x7fff2c128100 "3\300\216=D0=BC", nb_sectors=3Dnb_s=
ectors@entry=3D4)
    at block.c:2241
#13 0x00007f63d27d2d82 in bdrv_pread (bs=3D0x7f63d48b96e0, offset=3Doffse=
t@entry=3D
    0, buf=3Dbuf@entry=3D0x7fff2c128100, count1=3Dcount1@entry=3D2048) at=
 block.c:2303
#14 0x00007f63d27d3460 in find_image_format (pdrv=3D<synthetic pointer>,=20
    filename=3D0x7f63d48b6b40 "http://192.168.0.249/scratch/winxp.img",=20
    bs=3D<optimized out>) at block.c:533
#15 bdrv_open (bs=3D0x7f63d48b6cc0, filename=3Dfilename@entry=3D
    0x7f63d48b6b40 "http://192.168.0.249/scratch/winxp.img", options=3D
    0x7f63d48b76a0, options@entry=3D0x7f63d48b5980, flags=3D8258, drv=3Dd=
rv@entry=3D
    0x0) at block.c:1047
#16 0x00007f63d2806093 in drive_init (all_opts=3D0x7f63d48b2420,=20
    block_default_type=3DIF_NONE) at blockdev.c:698
#17 0x00007f63d297054b in drive_init_func (opts=3D<optimized out>,=20
    opaque=3D<optimized out>) at vl.c:1117
#18 0x00007f63d2a9a6f3 in qemu_opts_foreach (list=3D<optimized out>,=20
    func=3Dfunc@entry=3D0x7f63d2970530 <drive_init_func>, opaque=3Dopaque=
@entry=3D
    0x7f63d2e938f0 <pc_i440fx_machine_v1_5+48>,=20
    abort_on_failure=3Dabort_on_failure@entry=3D1) at util/qemu-option.c:=
1162
#19 0x00007f63d27b7b89 in main (argc=3D<optimized out>, argv=3D<optimized=
 out>,=20
    envp=3D<optimized out>) at vl.c:4201

---

For completeness:

(1) qemu from git (without your patches) works.

(2) I'm testing using the following command:

$ LD_LIBRARY_PATH=3D~/d/curl/lib/.libs \
  LIBGUESTFS_BACKEND=3Ddirect \
  LIBGUESTFS_QEMU=3D~/d/qemu/qemu.wrapper \
  ./run ./fish/guestfish -a http://192.168.0.249/scratch/winxp.img -i -v

where:

(a) ~/d/libguestfs contains libguestfs from git
(b) ~/d/curl contains curl-7_30_0-147-gae26ee3
(c) http://192.168.0.249/scratch/winxp.img is a Windows XP image
(d) qemu.wrapper is:

----------------------------------------------------------------------
#!/bin/sh -
qemudir=3D/home/rjones/d/qemu
exec $qemudir/x86_64-softmmu/qemu-system-x86_64 -L $qemudir/pc-bios "$@"
----------------------------------------------------------------------

Rich.

--=20
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rj=
ones
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW