CVE-2025-39681

Vulnerability 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. ]

CVSS Score

Affected Products

References

• https://git.kernel.org/stable/c/62f12cde10118253348a7540e85606869bd69432Patch
• https://git.kernel.org/stable/c/7207923d8453ebfb35667c1736169f2dd796772ePatch
• https://git.kernel.org/stable/c/873f32201df8876bdb2563e3187e79149427cab4Patch
• https://git.kernel.org/stable/c/a9e5924daa954c9f585c1ca00358afe71d6781c4Patch
• https://git.kernel.org/stable/c/d23264c257a70dbe021b43b3bc2ee16134cd2c69Patch
• https://git.kernel.org/stable/c/d8df126349dad855cdfedd6bbf315bad2e901c2fPatch
• https://git.kernel.org/stable/c/fb81222c1559f89bfe3aa1010f6d112531d55353Patch
• https://lists.debian.org/debian-lts-announce/2025/10/msg00007.htmlThird Party Advisory
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.htmlThird Party Advisory
• https://cert-portal.siemens.com/productcert/html/ssa-032379.html