# CVE-2026-98391: drm/xe: Guard page-fault worker with runtime PM check

> A race condition in the Linux kernel's Xe GPU driver can cause a system crash when a page-fault worker accesses a suspended device during VM teardown.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-98391, GHSA-v93p-6w5h-wmxx, UBUNTU-CVE-2026-98391

## What is CVE-2026-98391?

CVE-2026-98391 is a denial of service vulnerability in Linux, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

drm/xe: Guard page-fault worker with runtime PM check

During VM teardown, the VM's runtime PM reference is dropped
asynchronously, allowing the device to autosuspend while stale page
faults belonging to the now-dead VM are still queued. When the
page-fault worker later tries to ack one of these, it calls into
guc_ct_send_locked() on an already-suspended device, tripping:

  Assertion `!xe_pm_runtime_suspended(xe)` failed!
  WARNING at xe_device.c:1267 xe_device_assert_mem_access+0x11c/0x140 [xe]

A live VM/exec queue always holds a PM reference while it has
outstanding work, so if the device is suspended at ack time, the
owning context is already gone and the fault is stale.

Take a runtime PM reference across the entire pagefault
queue worker to safely deliver acks for torn-down VMs.

v3:
 - Move PM ref to the generic xe_pagefault_queue_work using
   guard(xe_pm_runtime)(xe) instead of tracking it in the GuC
   backend(Matt Brost).

v2:
 - Hold PM ref across the entire batch (begin/end) instead of per-ack.
   This prevents the device from autosuspending mid-batch, which would
   leave write_only acks written but the end flush skipped, and skip
   counter++, desyncing the cadence check.(Himal)
 - Add a comment explaining stale faults.(Himal)

(cherry picked from commit fcc2431d2213dc4d04250c4f1ae87d9c3ae0d455)
[Rodrigo: Added xe_device struct for compatibility while cherry-picking]

## Which versions are affected by CVE-2026-98391?


## How do I fix CVE-2026-98391?

Apply the vendor's patch.

## Is CVE-2026-98391 being exploited?

There is no known exploitation of CVE-2026-98391 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98391 and fix it if it is affected.

What it is: CVE-2026-98391 is a denial of service vulnerability in Linux, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98391 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98391/ (Markdown: https://insights.sbomify.com/CVE-2026-98391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98391
- OSV: https://osv.dev/vulnerability/CVE-2026-98391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98391/
Summaries are generated and may contain mistakes; the official description above is the record.