---
id: CVE-2026-23213
title: >-
  kernel: drm/amd/pm: Disable MMIO access during SMU Mode 1 reset
  (CVE-2026-23213)
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/amd/pm: Disable MMIO access during SMU Mode 1 reset

  During Mode 1 reset, the ASIC undergoes a reset cycle and becomes
  temporarily inaccessible via PCIe. Any attempt …
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-366
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 6
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
published: '2026-02-18'
updated: '2026-10-23'
sourceUpdated: '2026-10-23T11:17:26+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23213.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23213.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-23213'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2440642'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-23213'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-23213'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2026021800-CVE-2026-23213-c699@gregkh/T
  - url: 'https://git.kernel.org/stable/c/b2b9ac2bb2c5b5b0a39f7f422bbe12d3ea4ccf34'
  - url: 'https://git.kernel.org/stable/c/c1853ebbec980d5c05d431bfd6ded73b1363fd00'
  - url: 'https://git.kernel.org/stable/c/cd7ff7fd3e4b77f0b5a292e0926532eaa07c5162'
  - url: 'https://git.kernel.org/stable/c/0de604d0357d0d22cbf03af1077d174b641707b6'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00177
epssPercentile: 0.07133
ingestedAt: '2026-10-21T12:48:53.670Z'
---

## Overview

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

drm/amd/pm: Disable MMIO access during SMU Mode 1 reset

During Mode 1 reset, the ASIC undergoes a reset cycle and becomes
temporarily inaccessible via PCIe. Any attempt to access MMIO registers
during this window (e.g., from interrupt handlers or other driver threads)
can result in uncompleted PCIe transactions, leading to NMI panics or
system hangs.

To prevent this, set the `no_hw_access` flag to true immediately after
triggering the reset. This signals other driver components to skip
register accesses while the device is offline.

A memory barrier `smp_mb()` is added to ensure the flag update is
globally visible to all cores before the driver enters the sleep/wait
state.

(cherry picked from commit 7edb503fe4b6d67f47d8bb0dfafb8e699bb0f8a4)

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23213.json)

**kernel: drm/amd/pm: Disable MMIO access during SMU Mode 1 reset** — rated Moderate by Red Hat. Released 2026-02-18, updated 2026-10-23.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9

No fix planned:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9

## Remediation

Out of support scope