Description of problem:

On a machine having NFS trouble, 'qemu-img create' tries to create a new qcow2 image and when close() returns -EIO, but the error is silently ignored.


Version-Release number of selected component (if applicable):
qemu-img-0.12.1.2-2.113.el6.x86_64

How reproducible:
Not easily, as you have to make close() return error (I have a machine where this is happening for unknown reasons).


Steps to Reproduce:
1) break NFS  :)
2) run: qemu-img create -f qcow2 /path/to/file/on/nfs.qcow2 10G

  
Actual results:
# strace -f qemu-img create -f qcow2 /tmp/kvm_autotest_root/images/rhel5-32.qcow2 10G
execve("/usr/bin/qemu-img", ["qemu-img", "create", "-f", "qcow2", "/tmp/kvm_autotest_root/images/rh"..., "10G"], [/* 29 vars */]) = 0
brk(0)                                  = 0x2226000
[...]
write(1, "Formatting '/tmp/kvm_autotest_ro"..., 117Formatting '/tmp/kvm_autotest_root/images/rhel5-32.qcow2', fmt=qcow2 size=10737418240 encryption=off cluster_size=0
) = 117
open("/tmp/kvm_autotest_root/images/rhel5-32.qcow2", O_WRONLY|O_CREAT|O_TRUNC, 0644) = 3
write(3, "QFI\373\0\0\0\2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\20\0\0\0\2\200\0\0\0"..., 72) = 72
lseek(3, 65536, SEEK_SET)               = 65536
write(3, "\0\0\0\0\0\0\0\0", 8)         = 8
[...]
close(3)                                = -1 EIO (Input/output error)
exit_group(0)                           = ?
[root@virtlab105 default]# date
Thu Oct  7 15:30:46 EDT 2010
[root@virtlab105 default]# ls -l /tmp/kvm_autotest_root/images/rhel5-32.qcow2
-rw-r--r-- 1 root root 262144 Oct  7 15:27 /tmp/kvm_autotest_root/images/rhel5-32.qcow2
[root@virtlab105 default]# date
Thu Oct  7 15:30:52 EDT 2010
[root@virtlab105 default]# ls -l /tmp/kvm_autotest_root/images/rhel5-32.qcow2
-rw-r--r-- 1 root root 0 Oct  7 15:27 /tmp/kvm_autotest_root/images/rhel5-32.qcow2
[root@virtlab105 default]# 


Expected results:
qemu-img should return non-zero exit code and show an error message.