> Subject: Re: [PATCH v8 02/18] hw/usb/hcd-xhci: Add an auto-hub property and > leave it off > > Hi Jamin, > > On Mon, Nov 02, 2026 at 09:22:05AM +0000, Jamin Lin wrote: > > Add auto-hub and leave it off. hw_compat_11_1 turns it on, so an older > > machine type keeps the hub it has today and a guest saved by an older > > QEMU still loads. > > Reran the migration check from v7: with pc-q35-11.1, a guest saved without > the series loads on v8 with the hub in place, for qemu-xhci with four HID > devices and for q35 -usb with six. > > But this missed the 11.2 soft freeze, so in 12.0 pc-q35-11.2 is an old machine > type too, and hw_compat_11_1 (my suggestion on v7) doesn't cover it. Saved > with pc-q35-11.2 on master, both cases fail on v8: > > Unknown section or instance '0000:00:01.0/4/usb-hub' 0 > Unknown section or instance '0000:00:1d.7/6/usb-hub' 0 > > The entries from 02-05 want hw_compat_11_2 once the 12.0 machine types > are in. > > Junjie
Hi Junjie, Marc-André, and Gerd, Due to the QEMU code freeze and the planned 11.2 release in December, disabling automatic hub creation while keeping migration compatibility with older QEMU versions requires adding the property to hw_compat_11_2. We need to wait until after the QEMU 11.2 release for the maintainers to add hw_compat_11_2 to each machine type. The USB redirection server is my original upstream goal, and I think this task is independent of the automatic hub task. So, I want to split the auto-hub changes into a separate prerequisite patch series and send v9 after the QEMU 11.2 release. The USB redirection server common protocol series still needs rework on the device announcement and control transfer patches. I will send v9 next week and mention that it requires the patch series that disables automatic hub creation. This way, we can continue testing and reviewing the USB redirection server common protocol this month.(November) "If you agree, I will send v9 next week. Otherwise, I will wait until after the QEMU 11.2 release and then resend the full patch series as v9." Thanks, Jamin
