[Qemu-devel] core dump on networking and old pkgsrc patches

[Qemu-devel] core dump on networking and old pkgsrc patches

[Jeremy C. Reed]

This is a problem that may already be fixed.

I am using qemu 0.9.0 on NetBSD/amd64 -current. It is built using pkgsrc.
I know it is out of date. But qemu 0.9.0, 0.9.1, and qemu HEAD from 
subversion do not build on NetBSD without patches.

I emailed this list in November to ask how to submit patches. That thread 
starts here:
http://lists.gnu.org/archive/html/qemu-devel/2007-11/msg00845.html

Someone else attached patches for 0.9.1 here:
http://lists.gnu.org/archive/html/qemu-devel/2008-01/threads.html
(But no feedback)

I tried the latest qemu from subversion yesterday and see it still doesn't 
build on NetBSD.

What can I do to get the pkgsrc patches for NetBSD, DragonFly and pkgsrc 
integrated (as appropriate) into qemu?

Now to my current problem... whenever I attempt to ssh or ftp to my 
gateway (10.0.2.2 assigned by qemu) it core dumps. This is running FreeBSD 
4.9 and also DSL Linux 4.2.4.

gdb shows:

Core was generated by `qemu'.
Program terminated with signal 11, Segmentation fault.
#0  0x000000000046bfef in tcp_reass (tp=0x7f7ffb238180, ti=0xfb238180, 
m=0x0)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/slirp/tcp_input.c:207
207             if (ti == (struct tcpiphdr *)tp || ti->ti_seq != 
tp->rcv_nxt)
(gdb) bt
#0  0x000000000046bfef in tcp_reass (tp=0x7f7ffb238180, ti=0xfb238180, 
m=0x0)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/slirp/tcp_input.c:207
#1  0x000000000046cba8 in tcp_input (m=0x7f7ffb228800, iphlen=-8760, 
    inso=0x7f7ffb228850)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/slirp/tcp_input.c:1051
#2  0x0000000000407041 in qemu_send_packet (vc1=0x7f7ffb101eb0, 
    buf=0x7f7ff1b1f866 "RT", size=60)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/vl.c:2993
#3  0x000000000042be24 in ne2000_ioport_write (opaque=0x7f7ff1b1b220, 
addr=0, 
    val=4) at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/hw/ne2000.c:347
#4  0x0000000000404936 in cpu_outb (env=0x7f7ffb238180, addr=0, 
val=-737804918)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/vl.c:317
#5  0x0000000001b5d369 in code_gen_buffer ()
#6  0x000000000000002b in ?? ()
#7  0x0000000000475382 in cpu_x86_exec (env1=0x7f7ffb238180)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/cpu-exec.c:739
#8  0x000000000040b06a in main_loop ()
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/vl.c:5965
#9  0x000000000040c28f in main (argc=3, argv=0xc0fa4824)
    at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/vl.c:727

Re: [Qemu-devel] core dump on networking and old pkgsrc patches

[Blue Swirl]

On 7/1/08, Jeremy C. Reed <reed@reedmedia.net> wrote:
> This is a problem that may already be fixed.

Not yet, even though several people have tried and failed.

>  #0  0x000000000046bfef in tcp_reass (tp=0x7f7ffb238180, ti=0xfb238180,
>  m=0x0)
>     at /usr/pkgsrc/emulators/qemu/work/qemu-0.9.0/slirp/tcp_input.c:207
>  207             if (ti == (struct tcpiphdr *)tp || ti->ti_seq !=
>  tp->rcv_nxt)

SLIRP re-uses some of the 32 bit TCP/IP header fields as storage for
pointers. This works on a 32 bit host and in some lucky cases on a
x86-64.

Please visit
http://lists.gnu.org/archive/html/qemu-devel/2008-01/msg00725.html