CVE-2025-38520 — Improper Locking in Linux

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Don't call mmput from MMU notifier callback If the process is exiting, the mmput inside mmu notifier callback from compactd or fork or numa balancing could release the last reference of mm struct to call exit_mmap and free_pgtable, this triggers deadlock with below backtrace. The deadlock will leak kfd process as mmu notifier release is not called and cause VRAM leaking. The fix is to take mm reference mmget_non_…