On Tue, Feb 17, 2026 at 09:47:08 +0000, Daniel P. Berrangé wrote: > On Tue, Feb 17, 2026 at 10:29:38AM +0100, Peter Krempa wrote: > > On Thu, Jan 15, 2026 at 17:55:01 -0500, Peter Xu wrote: > > > v2: > > > - Added R-bs > > > - Updated description for removing zero-blocks [Markus] > > > - Squashed the "fd: to file" test removal into the 2nd patch > > > - I dropped the COLO patch, I have a local patch to remove colo migration > > > completely, but looks like we won't do it.. Let's leave it for later > > > but > > > do the rest first > > > > > > This series removes two deprecated features for 11.0. > > > > > > Please review, thanks. > > > > > > Peter Xu (2): > > > migration: Remove zero-blocks capability > > > migration: Remove fd: support on files > > > > > > docs/about/deprecated.rst | 20 ------------- > > > > Note that per the 'MAINTAINERS' file, changes to any deprecations ought > > to be CC'd to the libvirt list for visibility. > > > > In this case we've forgotten about the deprecation and didn't fix it > > before the qemu cahnge was pushed. I'll send out patches soon, but keep > > in mind to *always* CC the libvirt list with deprecations. > > I'm suprised to see libvirt broken at all here. > > AFAIR, the 'fd:' protocol inadvertantly gained support for targetting > plain files, which the deprecation aimed to then revert (remove). The > actual removal though seems to have targetted anything which is not a > socket, which includes pipes, which libvirt was using.
Libvirt is using pipes for *most* cases, but not all. There is one code path (virsh restore without compression or cache bypass, when residing on an actual filesystem (not a root squashed NFS)) which still can pass a file FD to the migration code as 'fd:'. In all other cases we do pass in a pipe in one way or another (via the compression program, virFileWrapper (mandatorily used on equivalents of 'virsh save', or the helper process used to access root-squashed NFS). The code is not easy to follow because there are numerous layers where the wrapping of the file into a pipe can happen, one of which is right next to the migration code. I'll soon post patches. Anyways, my point was that notifications about deprecated and removed features ought to be CCd to the libvirt list regardless of perceived impact on libvirt.
