CVE-2025-39681
x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper
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. ]
INFO
Published Date :
Sept. 5, 2025, 6:15 p.m.
Last Modified :
Sept. 5, 2025, 6:15 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2025-39681
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Apply the provided kernel patches to the Linux system.
- Reboot the system after applying the patches.
- Verify that the system boots without division by zero errors.
References to Advisories, Solutions, and Tools
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information, practical solutions, and valuable tools related to
CVE-2025-39681.
CWE - Common Weakness Enumeration
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specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-39681 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-39681
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2025-39681 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-39681 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 05, 2025
Action Type Old Value New Value Added 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. ] Added Reference https://git.kernel.org/stable/c/7207923d8453ebfb35667c1736169f2dd796772e Added Reference https://git.kernel.org/stable/c/873f32201df8876bdb2563e3187e79149427cab4 Added Reference https://git.kernel.org/stable/c/a9e5924daa954c9f585c1ca00358afe71d6781c4 Added Reference https://git.kernel.org/stable/c/d23264c257a70dbe021b43b3bc2ee16134cd2c69 Added Reference https://git.kernel.org/stable/c/d8df126349dad855cdfedd6bbf315bad2e901c2f Added Reference https://git.kernel.org/stable/c/fb81222c1559f89bfe3aa1010f6d112531d55353