Hi
I apologize for the lack of details, but when running qemu-system-arm with a Linaro vexpress kernel, I get frequent stalls which make it barely usable :-/
I'm starting qemu-linaro on a fast (c1.medium) EC2 instance which seems to behave normally in general. It's maverick based and I use qemu-linaro 2011.03: 0.14.50-2011.03-1-0ubuntu1~ppa10.10.1
I'm creating a SD card image with linaro-media-create with something like:
./linaro-media-create --image_file qemu.img --hwpack hwpack_linaro-vexpress_20110309-0_armel_supported.tar.gz --image_size 10G --dev vexpress --rootfs ext4 --binary linaro-n-developer-tar-20110309-0.tar.gz --hwpack-force-yes.
I'm launching qemu with something like:
qemu-system-arm -M vexpress-a9 -kernel ~/vmlinuz-2.6.38-1000-linaro-vexpress -nographic -append "serialtty=ttyAMA0,38400 console=ttyAMA0,38400 root=/dev/mmcblk0p2" -initrd ~/initrd.img-2.6.38-1000-linaro-vexpress -sd qemu.img
and install openssh; I connected over a -redir 2022::22 connection and run apt-get install from either serial console or from the SSH session, in both cases it hangs pretty badly, but it seems that the console session remains a bit more responsive to key presses.
Thanks,
As a data point, I tried running the images from:
http://
and they didn't hang (with the same qemu-linaro version).
The difference are numerous:
* different model
* quite different kernels
* different userspaces (notably ARMv7 Thumb-2 vs. ARMv4T)
* different root types (notably SD versus SCSI over PCI)
I tried booting the Debian image using -sd instead of -hda, but didn't work -- the module isn't in the kernel nor in the initramfs, so no SD card gets detected.
Booting the Debian image using the Ubuntu kernel + initrd and -hda wouldn't work as vexpress has no PCI, so I tried with -sd (so basically a Debian userspace and everything else from Ubuntu); this seemed pretty stable to me. Under load I did see some much shorter stalls when doing CPU intensive tasks, but much less so, they felt more natural and didn't trigger while just apt-get update-ing for instance.
So this might very well be a problem with ARMv7 + Thumb-2 userspace :-/