Xen event channel interrupt core
The plumbing that delivers virtual interrupts ("event channels") between the Xen hypervisor and a Linux guest, used whenever Linux runs as a Xen VM on cloud, server, automotive, or embedded Xen deployments. It is the foundation that Xen paravirtualised devices (network, block, console, etc.) rely on to signal the guest kernel.
recommendation
It should stay because this is the core interrupt-delivery mechanism that lets Linux run as a Xen guest (and in some cases as the Xen host), and there is no replacement for it. Active maintenance is visible as recently as 2025, with stable-tree bug fixes landing for things like VIRQ binding and IRQ migration, and Xen itself shipped a new 4.21 release in November 2025 aimed at cloud, automotive, and embedded use.
repository signals
sources
- spinics.net
2025 stable patch traffic included a bug fix for xen/events ('Return -EEXIST for bound VIRQs'), indicating active maintenance rather than retirement.
- spinics.net
2025 stable patch traffic included another xen/events fix ('Update virq_to_irq on migration'), showing current upstream attention to runtime behavior.
- docs.kernel.org
Current kernel documentation still exposes Xen event-channel tuning knobs such as xen.event_eoi_delay, xen.event_loop_timeout, and xen.fifo_events, showing the subsystem remains supported and user-visible.
- qemu.org
Current QEMU documentation describes Xen guest support, including event channel delivery and Xen PV devices, so the Linux Xen guest interrupt path is still relevant in new virtualized deployments.
- linuxfoundation.org
The Xen Project announced Xen 4.21 on November 19, 2025 and positioned Xen for cloud, server, automotive, and embedded workloads, supporting the view that Xen remains in active deployment niches.
codex reasoning notes (technical)
Local shell inspection (`rg`, `sed`, `git -c safe.directory ... log`) shows this directory is Xen guest event-channel interrupt core code, built into `events.o`, not dead scaffolding. Web search was used to gather public maintenance/deployment evidence: two spinics stable patch threads show 2025 bug-fix activity for xen/events; docs.kernel.org confirms current kernel-exposed Xen event-channel parameters; QEMU docs confirm current Xen guest/event-channel support; Linux Foundation/Xen release material shows Xen 4.21 was released for ongoing cloud/embedded/automotive use. No removal series surfaced in the lore/spinics search pass. This is not sellable hardware, so `hardware_still_sold_new_in_2025` is false and `last_widely_available_year` is null, but the ABI is still relevant for contemporary Xen-based VM and embedded deployments. No natural replacement driver exists because this code implements the Xen-specific event-channel interrupt mechanism itself.