Re: [Qemu-devel] and now bus error for i386 guest

[Shaddy Baddah <shaddy.baddah@g2microsystems.com>]

HI,

Blue Swirl wrote:
> On 11/14/07, Shaddy Baddah <shaddy.baddah@shaddybaddah.name> wrote:
>> Hi again,
>>
>> After further culling the target list, I was able to install qemu on my
>> sun4u host.
>>
>> However, running it, I get a bus error. See below for details:
>>
>> $ /opt/qemu-cvs/bin/qemu -m 128 -cdrom
>> ~/KNOPPIX_V5.1.1CD-2007-01-04-EN.iso -vnc :1
>> Bus error
> 
> For some reason, Sparc Linux host is not working. I think Sparc Solaris is OK.

Yes, I do recall that I was able to get this working on Sparc Solaris. 
Anyway, when I get more time, I will have a better stab at debugging 
this. I got a start on this today, and here is a bit of cut and paste 
that may or may not be insightful. The address for env1 looks questionable:

shaddy@localhost:~/qemu-cvs/qemu-build$ gdb --args ./i386-softmmu/qemu 
-hda ../../KNOPPIX_V5.1.1CD-2007-01-04-EN.iso -L ../qemu/pc-bios
GNU gdb 6.6.90.20070912-debian
Copyright (C) 2007 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
<http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "sparc-linux-gnu"...
Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) run
Starting program: /home/shaddy/qemu-cvs/qemu-build/i386-softmmu/qemu 
-hda ../../KNOPPIX_V5.1.1CD-2007-01-04-EN.iso -L ../qemu/pc-bios
[Thread debugging using libthread_db enabled]
[New Thread 0xf7f7b550 (LWP 9363)]

Program received signal SIGBUS, Bus error.
[Switching to Thread 0xf7f7b550 (LWP 9363)]
cpu_x86_exec (env1=0x2) at /home/shaddy/qemu-cvs/qemu/cpu-exec.c:307
307                 if (env->exception_index >= 0) {
(gdb) info threads
* 1 Thread 0xf7f7b550 (LWP 9363)  cpu_x86_exec (env1=0x2)
     at /home/shaddy/qemu-cvs/qemu/cpu-exec.c:307
(gdb)

HTH,
Shaddy

PS: couldn't this also be debugged from within qemu VM running Debian 
Sparc, for those that don't have access to a real machine? I got a start 
on this today as well (because I don't always have access to the Sun 
Ultra box). Seems stable, and I was able to get a start on a compile, 
that is currently still going.