---
id: CVE-2025-71119
title: 'powerpc/kexec: Enable SMT before waking offline CPUs'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  powerpc/kexec: Enable SMT before waking offline CPUs

  If SMT is disabled or a partial SMT state is enabled, when a new kernel
  image is loaded for kexec, on reboot the f…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 482fa21635c8832db022cd2d649db26b8e6170ac <
    7cccd82a0e4aad192fd74fc60e61ed9aed5857a3
  - >-
    Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 <
    d790ef0c4819424ee0c2f448c0a8154c5ca369d1
  - >-
    Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 <
    f0c0a681ffb77b8c5290c88c02d968199663939b
  - >-
    Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 <
    0d5c9e901ad40bd39b38e119c0454b52d7663930
  - >-
    Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 <
    c2296a1e42418556efbeb5636c4fa6aa6106713a
  - Linux 15141adf85b14a7cff7abba1cb983f0bf17e3b36
  - Linux >= 6.1.72 < 6.1.160
  - Linux >= 6.5.12 < 6.6
  - Linux 6.6
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:14:17.903207Z'
published: '2026-01-14'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:23:08.824Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-71119'
references:
  - url: 'https://git.kernel.org/stable/c/7cccd82a0e4aad192fd74fc60e61ed9aed5857a3'
  - url: 'https://git.kernel.org/stable/c/d790ef0c4819424ee0c2f448c0a8154c5ca369d1'
  - url: 'https://git.kernel.org/stable/c/f0c0a681ffb77b8c5290c88c02d968199663939b'
  - url: 'https://git.kernel.org/stable/c/0d5c9e901ad40bd39b38e119c0454b52d7663930'
  - url: 'https://git.kernel.org/stable/c/c2296a1e42418556efbeb5636c4fa6aa6106713a'
tags:
  - cve.org
epss: 0.00146
epssPercentile: 0.03862
ingestedAt: '2026-11-05T22:38:32.049Z'
---

## Overview

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

powerpc/kexec: Enable SMT before waking offline CPUs

If SMT is disabled or a partial SMT state is enabled, when a new kernel
image is loaded for kexec, on reboot the following warning is observed:

kexec: Waking offline cpu 228.
WARNING: CPU: 0 PID: 9062 at arch/powerpc/kexec/core_64.c:223 kexec_prepare_cpus+0x1b0/0x1bc
[snip]
 NIP kexec_prepare_cpus+0x1b0/0x1bc
 LR  kexec_prepare_cpus+0x1a0/0x1bc
 Call Trace:
  kexec_prepare_cpus+0x1a0/0x1bc (unreliable)
  default_machine_kexec+0x160/0x19c
  machine_kexec+0x80/0x88
  kernel_kexec+0xd0/0x118
  __do_sys_reboot+0x210/0x2c4
  system_call_exception+0x124/0x320
  system_call_vectored_common+0x15c/0x2ec

This occurs as add_cpu() fails due to cpu_bootable() returning false for
CPUs that fail the cpu_smt_thread_allowed() check or non primary
threads if SMT is disabled.

Fix the issue by enabling SMT and resetting the number of SMT threads to
the number of threads per core, before attempting to wake up all present
CPUs.

## Affected

- `Linux >= 482fa21635c8832db022cd2d649db26b8e6170ac < 7cccd82a0e4aad192fd74fc60e61ed9aed5857a3`
- `Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 < d790ef0c4819424ee0c2f448c0a8154c5ca369d1`
- `Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 < f0c0a681ffb77b8c5290c88c02d968199663939b`
- `Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 < 0d5c9e901ad40bd39b38e119c0454b52d7663930`
- `Linux >= 38253464bc821d6de6bba81bb1412ebb36f6cbd1 < c2296a1e42418556efbeb5636c4fa6aa6106713a`
- `Linux 15141adf85b14a7cff7abba1cb983f0bf17e3b36`
- `Linux >= 6.1.72 < 6.1.160`
- `Linux >= 6.5.12 < 6.6`
- `Linux 6.6`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.