Comment 1 for bug 1027525

I ran strace while running the test and I see few times:

open("/srv/kvm/iso/ubuntu-12.04-server-amd64.iso", O_RDONLY|O_NONBLOCK) = 12
fstat(12, {st_mode=S_IFREG|0666, st_size=717533184, ...}) = 0
close(12)

But the final open looks like this:

open("/srv/kvm/iso/ubuntu-12.04-server-amd64.iso", O_RDWR|O_DSYNC|O_CLOEXEC) = -1 EROFS (Read-only file system)

For some reason, the O_RDRW flag was requested.