[PATCH QEMU HCI-8.0 v8 00/14] usb-host: support CPR migration

[Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>]

v7 -> v8:

Fixes for the issues from Sashiko's v7 review that were verified real:
https://sashiko.vzint.dev/#/patchset/20261006-usb-host_v3-v7-0-044f668789a1@virtuozzo.com

Functional fixes:
- hand off: the cpr-transfer target now marks the device as not owned
  until .post_load() completes the takeover, so a target failing the
  incoming migration no longer resets the shared device and releases
  its interfaces underneath the still-live source on exit
- drain: re-cancel in-flight iso URBs on every reap iteration --
  reaping an iso IN URB wakes the endpoint, and xHCI can submit fresh
  iso URBs mid-drain, which previously escaped cancellation
- drain: an OUT transfer cancelled after moving some data is now
  delivered with the actually-consumed length instead of the full
  submit-time size

Minor hardening:
- usb_host_req_cpr_replay() is gated on an active drain
- NULL-dh guard in the CPR target's interface reclaim
- unrealize() restarts the event reaping it had stopped, when it still
  owns the device

v7: http://lore.virtuozzo.com/20261006-usb-host_v3-v7-0-044f668789a1@virtuozzo.com

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
---
Andrey Drobyshev (14):
      usb-host: don't leak hostdev FD on open failure #VSTOR-137800
      usb-host: don't leak config descriptor on claim failure #VSTOR-137800
      usb-host: add migration blocker for CPR modes #VSTOR-137800
      usb-host: preserve hostdev FD during CPR migration #VSTOR-137800
      usb-host: factor out usb_host_reap_xfers() #VSTOR-137800
      usb-host: drain in-flight URBs across CPR #VSTOR-137800
      usb-host: re-issue drained URBs if CPR is aborted #VSTOR-137800
      usb-host: skip product-string read on CPR incoming #VSTOR-137800
      usb-host: factor out usb_host_start_events() #VSTOR-137800
      usb-host: hand off the device across cpr-transfer #VSTOR-137800
      usb: migrate the interface altsetting #VSTOR-137800
      usb-host: reconfigure endpoints on CPR incoming #VSTOR-137800
      hcd-xhci: resync isochronous endpoints after CPR #VSTOR-137800
      usb-host: make CPR migration blocker conditional #VSTOR-137800

 hw/usb/bus.c         |  36 +++
 hw/usb/hcd-xhci.c    |  25 +++
 hw/usb/host-libusb.c | 605 ++++++++++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 613 insertions(+), 53 deletions(-)
---
base-commit: f3c1d9ef263edfab8d2a273078493bb766dcf8f8
change-id: 20260914-usb-host_v3-bbfea86d1dad

Best regards,
--  
Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>