kvm > 61 segfaults when started with a bridged tap

[iMil <imil@imil.net>]

Hi,

Since I upgraded my ubuntu machine to 8.04, 
/usr/local/bin/qemu-system-x86_64 segfaults when starting with -net 
tap,ifname=tap0 flags. Of course, it's been recompiled.

$ sudo /usr/local/bin/qemu-system-x86_64 /data/virt/netbsd.img -net 
nic,macaddr=00:56:01:02:03:04 -net tap,ifname=tap0,script=/etc/qemu-ifup
Segmentation fault

I see the same behaviour with any NIC, and for kvm from -62 to -67 (I 
tested each version). 
Downgrading to kvm-61 fixes the problem. It seems like there's a similar 
bug report here: 
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=476469

The VM also start correctly with qemu.

$ modinfo kvm-intel
filename:       /lib/modules/2.6.24-16-generic/extra/kvm-intel.ko
license:        GPL
author:         Qumranet
version:        kvm-67
srcversion:     2E2C88C6F09E216FDAA6797
depends:        kvm
vermagic:       2.6.24-16-generic SMP mod_unload 586
parm:           bypass_guest_pf:bool
parm:           enable_vpid:bool
parm:           flexpriority_enabled:bool

$ uname -a
Linux tatooine 2.6.24-16-generic #1 SMP Thu Apr 10 13:23:42 UTC 2008 i686 
GNU/Linux

$ cat /proc/cpuinfo
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 15
model name	: Intel(R) Core(TM)2 CPU          6300  @ 1.86GHz
stepping	: 6
cpu MHz		: 1596.000
cache size	: 2048 KB
physical id	: 0
siblings	: 2
core id		: 0
cpu cores	: 2
fdiv_bug	: no
hlt_bug		: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 10
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca 
cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe lm 
constant_tsc arch_perfmon pebs bts pni monitor ds_cpl vmx est tm2 ssse3 
cx16 xtpr lahf_lm
bogomips	: 3736.56
clflush size	: 64

processor	: 1
vendor_id	: GenuineIntel
cpu family	: 6
model		: 15
model name	: Intel(R) Core(TM)2 CPU          6300  @ 1.86GHz
stepping	: 6
cpu MHz		: 1596.000
cache size	: 2048 KB
physical id	: 0
siblings	: 2
core id		: 1
cpu cores	: 2
fdiv_bug	: no
hlt_bug		: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 10
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca 
cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe lm 
constant_tsc arch_perfmon pebs bts pni monitor ds_cpl vmx est tm2 ssse3 
cx16 xtpr lahf_lm
bogomips	: 3733.37
clflush size	: 64

Interesting packages

ii  bridge-utils                                 1.2-2
ii  iproute                                      20071016-2ubuntu1
ii  libc6                                        2.7-10ubuntu3

Hope this helps,

regards

----------------------------------------
Emile "iMil" Heitor <imil@home.imil.net>                                  _
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