In the Linux kernel, the following vulnerability has been resolved: x86/mm: Don't apply va_align to hugetlb mappings on AMD F15h get_align_mask()… (CVE-2026-98729)

The vulnerability in the Linux kernel's x86 memory management subsystem was due to the function get_align_bits() adding va_align.bits even for hugetlbfs mappings, despite get_align_mask() returning huge_page_mask_align() for hugetlbfs. This caused vm_unmapped_area() to return addresses not aligned to huge page boundaries, leading __unmap_hugepage_range() to trigger a BUG_ON condition when clearing huge pages. The issue affects AMD F15h processors including Carrizo and FX-8370E. The resolution was to pass the file pointer to get_align_bits() and skip address randomization for hugetlbfs, preventing misaligned addresses and kernel crashes.

The vulnerability could cause kernel crashes (BUG_ON) during huge page teardown on affected AMD processors, potentially leading to system instability or denial of service. There is no indication of code execution or privilege escalation from the provided data.

A fix has been applied in the Linux kernel to correct the alignment handling for hugetlb mappings on AMD F15h processors. Users should update to the fixed kernel version once available. No additional mitigation steps are indicated.