ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled

Kernel Updated 02 Oct 2025

Summary

31/05/2021

Disclosed on

N/A

Severity

No i

Fix available

Unrated

Severity

Not published

CVSS Score

GSD-2021-1000019: ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled. Affects Kernel versions >= 2a15ba82fa6ca3f35502b3060f22118a938d2889, < 5965ac11b1d5fcb38464728931649cd9df79c7c9. No fix is published. How to fix ↓

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Background

The vulnerability affects the Kernel package in the Linux ecosystem. The Kernel is the core component of the operating system that manages system resources and provides an interface for applications to interact with the hardware. It is responsible for memory management, process scheduling, device drivers, and other essential functions. The vulnerability specifically impacts the mm (memory management) subsystem of the Kernel.

Vulnerability Detail

The vulnerability arises when DEBUG_KMAP_LOCAL is enabled in the ARM architecture. It leads to a reduction in the maximum number of CPUs supported by the system. This reduction can potentially impact the performance and scalability of multi-core systems. The vulnerability has been addressed in Linux Kernel version v5.11.16 by commit 5965ac11b1d5fcb38464728931649cd9df79c7c9. It was introduced in version v5.11 by commit 2a15ba82fa6ca3f35502b3060f22118a938d2889.

How To Fix

No fixed version is published for this vulnerability.

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Workaround

There is no specific workaround mentioned for this vulnerability.

Conclusion

The ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled vulnerability affects the Kernel package in the Linux ecosystem. It can lead to a reduction in the maximum number of CPUs supported by the system, potentially impacting the performance and scalability of multi-core systems. It is recommended to update the Linux Kernel to version v5.11.16 or later to mitigate the vulnerability. For further support on vulnerability remediation, you can reach out to DevNack.com.

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