Compute startup and driver interface. Instance startup processing on compute restart is now delegated to the virt drivers themselves, restructuring ~840 lines in the compute manager and libvirt driver. A companion reproducer for vTPM startup validation lands alongside it. Image metadata also learned to accept hw_firmware_stateless=True for the BIOS firmware type.

Bug fixes. The websocket proxy no longer mutates global config (fixed on both master and a stable branch), the API stops returning empty attachment_id values on volume attachments, and QEMU_IMG_LIMITS process limits become configurable across three branches. Smaller fixes cover a service_ref destroy check plus functional-test stabilization and speedups.

Maintenance. Dead code from the old image v1 API path and UpdateGlanceImage was removed, along with stale policy and cursive doc references.

Bug fixes. Two matching patches fix mutation of global config in the websocket proxy, landing on master and a stable branch. The API now returns 400 rather than a server error for invalid locked-memory properties, and QEMU_IMG_LIMITS process limits become configurable rather than hardcoded. A test-only fix addresses intermittent 409s in TestGracefulShutdown.

Elsewhere. The cyborg-tempest job is renamed to cyborg-tempest-py3.

Feature and config cleanup. The long-unused shutdown_terminate instance flag was removed, and the libvirt driver dropped its dependency on [libvirt] num_memory_encrypted_guests, deriving the limit from libvirt itself instead. Several rounds of dead-code removal and type fixes in privsep, utils, and libvirt logging round out the maintenance sweep, along with a pyproject packaging update.

Bug fixes. The websockify proxy no longer mutates global config on each connection, and noVNC traffic logging is now gated on debug=True. On the compute side, init_host pre-loads flavor and system_metadata to avoid repeated lazy loads, live-migration ensures resource limits are set before _call_livem_checks_on_host, and the security-group port query now restricts returned fields. Smaller fixes address a CLI-exit stacktrace, a mis-scoped mock, and a regression test for bug #2153425.

Scheduler hints hardening. Internal _nova-prefixed scheduler hints are now stripped on server create, with the same fix landed four times across active branches as backports. Elsewhere on the API side, a bug was fixed where multiple security groups sharing the same name within a project caused errors, with a dedicated reproducer test added for bug 2105896.

Testing and stability. A substantial (~480 line) functional test suite now exercises graceful shutdown of the compute service. An intermittent test_refresh_nfs_swap_cache_stale failure was fixed, and the nova-alt-configurations job was reworked. On the runtime side, daemon mode now restores the fork start method on Python 3.14, restoring compatibility with the upcoming interpreter.

Maintenance. Release notes builds were sped up via a small docs configuration change.

Bug fixes. Several long-standing edge cases got cleaned up. Resize was tightened to reject unpermitted flavors, port handling was fixed so that an error while updating a port on a multi-network instance no longer leaves the port hanging around, and an AttributeError in Service.stop() during early-startup shutdown was patched. A separate fix addresses an error that surfaced when multiple security groups in the same project shared a name. Each fix landed alongside a regression or reproducer test.

Libvirt and config surface. The libvirt driver gained a new config option for the live migration monitor interval, giving operators a knob over how frequently migrations are polled. A small libvirt utility that no longer had callers was dropped.

Maintenance. Cell URL parsing and Host header parsing were both reworked to use shared oslo.utils helpers instead of in-tree code. On the CI side, the graceful-shutdown jobs picked up irrelevant-files rules, and a flaky resize-reschedule functional test got more generous wait retries.

Threading migration. Eventlet imports are now poisoned when running in native threading mode, hardening the ongoing move off eventlet by making accidental imports fail loudly rather than silently re-introducing greenlet behavior.

Bug fixes. A handful of guest- and storage-path bugs landed: swap disk creation is no longer skipped on NFS during cold migration; the LVM image creation path no longer hangs on an interactive prompt; the RFB/VNC code now refuses to read up to 4 GiB of reason text from a remote endpoint; and an error triggered by duplicate security group names within a project was resolved. A reproducer test for bug 2105896 was also added.

Docs and CI. A substantial new document lands agentic-coding guidance for contributors working with AI assistants on Nova. On the CI side, the nova-vtpm job drops to tempest_concurrency=1, the coverage job gets another timeout bump, a stable-only grenade-multinode fix lands, and a stray log-message typo is corrected.

Quotas, security groups, and ports. Several user-facing correctness fixes landed in the API and resource-tracker neighborhood. User-scoped quota usage counts are now computed correctly, security-group lookups no longer fall over when two groups in the same project share a name, and a regression where ports remained allocated after a failed multi-network update was repaired. get_flavor_by_flavor_id() was also refactored to require an explicit context, tightening an internal contract used across the scheduler and compute managers.

Stability and hygiene. A metadata-proxy change stops the shared secret from being written to logs, and exc_info logging in image deletion was fixed. Two reproducer tests for outstanding bugs (2152697 and 2105896) merged, and CI noise from eventlet deprecation warnings was further muted.