Max Reitz <address@hidden> writes:
So I guess it's my turn to give yet another opinion (or just something
in between of what has been already said).
First, I'm fine with this patch, or at least the idea as there were
yet some quirks.
Yes, the patch has (fixable) issues. It's really just a sketch that
happens to work in common cases :)
But I oppose turning the warning into an error eventually. I want to
be able to use -hda $filename and it should work. As Kevin said, a
warning alone will not help a lot, though. I don't know about that, I
think it should work. This warning should only appear when you're
using qemu directly because management tools should already use -drive
with format= or driver=; and if you're using qemu directly you should
be watching stderr.
The only way I'd be fine with turning this into an error would be to
make an exception for -hda and the like. There were already plans of
introducing pseudo block drivers for format and protocol probing; if
we do that we can use those block drivers for -hda. We should still
emit the warning, but in my opinion it should never be an error with
-hda, -cdrom etc.. For me, this is not about backwards compatibility
but because I'm using -hda myself.
Examples of usage that is just fine (no warning):
* -hda test.qcow2
Fine as long as test.qcow2 is really qcow2 (as it should!), and
either specifies a backing format (as it arguably should), or the
backing file name is sane.
* -hda disk.img
Fine as long as disk.img is really a disk image (as it should).
* -hda /dev/mapper/vg0-virtdisk
Fine as long as the logical volume is raw. Not actually implemented
in my patch, but it's easy enough to do.
Can you give me a few examples from your usage that triggers the
warning?