Re: [Qemu-devel] [BUG] QEMU crashes when 64bit BAR is present

[Alexey Korolev]

On 10/12/12 20:22, Gerd Hoffmann wrote:
> On 12/10/12 03:05, Alexey Korolev wrote:
>> Hi,
>>>> It is a 64bit guest OS.
>>>> I've upgraded to RHEL 5.8 and still have the same problem.
>>> My rhel5 is 32bit.
>>>
>>>> Could you please send me a qemu command line you are running?
>>> qemu-default -m 512 -hda /vmdisk/guests/rhel5.img -device
>>> ivshmem,size=128M,shm=ivshmem.root
>> Could you please set the parameter use64=1 ?
> It's the default (except when using -M pc-$old), and according to lspci
> the guest sees a 64bit bar.
Correct. Just noticed that the default option use64 is 1.
>> I guess 64bit OS might also be important. I don't have a 32 bit version at 
>> the moment to check whether it fails or not.
> both 32bit and 64bit rhel5 installer isos boot just fine for me.
Installers are different case - the issue may not occur with installers.

It is easiest to reproduce the issue on a given configuration. I think I gave a 
pretty concise description of our case.

To reproduce the problem get:
A Centos 5.8 64bit Linux  (Centos 5.5 fails in the same way as well)
Get the latest qemu checkout (alternatively qemu 1.3.0 and 1.2.0 fail in a very 
similar way as well)

Try running
/usr/bin/qemu -enable-kvm -m 4096 -smp 1,sockets=1,cores=1,threads=1 -name 
Cent5 -nodefconfig -nodefaults -chardev
socket,id=charmonitor,path=/var/lib/libvirt/qemu/Cent5.monitor,server,nowait 
-mon chardev=charmonitor,id=monitor,mode=readline -rtc base=utc
-boot c -drive 
file=/patch_to_centos_5_8.ing,if=none,id=drive-ide0-0-0,format=raw -device
ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -vnc 127.0.0.1:0 -k 
en-us -vga std -device
ivshmem,size=128M,use64=1,shm,bus=pci.0,multifunction=on,addr=0x5.0x0 -device
virtio-balloon-pci,id=balloon0,bus=pci.0,multifunction=on,addr=0x4.0x0

and your guest will either hang or qemu process be terminated with an assertion 
message.