On Fri, Jun 22, 2018 at 07:54:00PM +0200, Kevin Wolf wrote:
Am 22.06.2018 um 17:40 hat Daniel P. Berrangé geschrieben:
On Fri, Jun 22, 2018 at 04:25:13PM +0200, Kevin Wolf wrote:
This was in fact one release longer than our deprecation policy says. Are we serious about the deprecation policy or aren't we?
I might consider reverting a change if it turned out that this requires some massive work in libvirt. But I think this one should be rather easy to fix in libvirt until 3.0 is released.
I've got a patch mostly ready that converts libvirt to setting these things on the frontend device, however, I've got some queries...
- usb-storage - doesn't appear to support geometry or werror/rerror
Will we loose functionality by stopping use of -drive for werror
Loosing geometry feels relevant too, unless it was already ignored when set opf -drive ?
You're right, usb-storage doesn't allow using -device to specify these, and it does use the values from -drive.
For werror/rerror, we should clearly implement the option forwarding to scsi-disk so that you can make use of it.
This missing werror item looks like a blocker for libvirt to be able to switch to using -blockdev without a regression.
I'm not sure how sane specifying a non-standard CHS geometry for a USB stick actually is. As an additional difficulty, usb-storage internally creates a scsi-disk device (not scsi-hd), which is also considered legacy and doesn't support the geometry options either, so it's not just simple forwarding. We removed an actual feature there, but that feature was probably never intended nor used.
If someone comes up with a compelling reason why they really need to configure the CHS geometry of their USB sticks, I guess we can do it. My real USB sticks I tested don't even support MODE_PAGE_HD_GEOMETRY (though they have MODE_PAGE_FLEXIBLE_DISK_GEOMETRY).
I don't think libvirt has a compelling reason. The ability to set CHS on usb-storage is just something we got for free because it used the same -drive syntax as other disk device frontends. It would be nice to avoid the regression but I doubt people will actually notice in practice as usb-storage users are few & far between, and even fewer of those will care about CHS. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|