vulnerability

Oracle Linux: CVE-2025-39681: ELSA-2025-25754: Unbreakable Enterprise kernel security update (IMPORTANT) (Multiple Advisories)

Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
Sep 5, 2025
Added
Nov 11, 2025
Modified
Nov 13, 2025

Description

In the Linux kernel, the following vulnerability has been resolved:
x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper
Since
923f3a2b48bd ("x86/resctrl: Query LLC monitoring properties once during boot")
resctrl_cpu_detect() has been moved from common CPU initialization code to
the vendor-specific BSP init helper, while Hygon didn't put that call in their
code.
This triggers a division by zero fault during early booting stage on our
machines with X86_FEATURE_CQM* supported, where get_rdt_mon_resources() tries
to calculate mon_l3_config with uninitialized boot_cpu_data.x86_cache_occ_scale.
Add the missing resctrl_cpu_detect() in the Hygon BSP init helper.
[ bp: Massage commit message. ]

Solution

oracle-linux-upgrade-kernel-uek
Title
NEW

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