Hello all, I have to consult you a qemu-img's problem.
Is this reasonable to create a file which is larger than the available size of the fs by qemu-img cmd ?
When I use qemu-img create a file which is larger than the available size of the fs, the creation is completed succesfully.
However when I use this file in guest as a guest's disk, and write beyond the size the host file can provides, the guest was paused by qemu-kvm or libvirt and was in maybe a infinite circle where the guest just can't be used except I detach the disk from guest or destroy the guest.
I read the qemu-img's code and found it just create the file as we required and doesn't check if the size we specify is reasonable.But this may let the guest in a risk of meeting the problem I describe above.
Exp: [root@build mytest]# df -ah /mytest/ Filesystem Size Used Avail Use% Mounted on /dev/sdb2 2.0G 3.1M 1.9G 1% /mytest [root@build mytest]# qemu-img create -f raw test.raw 3G Formatting 'test.raw', fmt=raw size=3221225472 [root@build mytest]# ls -l test.raw -rw-r--r--. 1 root root 3221225472 May 8 12:23 test.raw [root@build mytest]# Thank you. Best Regards Xinghai Yu
