CVE-2026-68265

In the Linux kernel, the following vulnerability has been resolved:

drm/xe/vm: Fix BO prefetch with CONSULT_MEM_ADVISE_PREF_LOC

When prefetch region is DRM_XE_CONSULT_MEM_ADVISE_PREF_LOC for a BO VMA,
the code used it as an index into region_to_mem_type[], causing an
out-of-bounds access since the value is -1.

Resolve the preferred location for BO VMAs directly: local VRAM on dGFX
(using the BO's tile placement) or system memory on iGPU.

Discovered using AI-assisted static analysis confirmed by Intel Product
Security.

v2:
-Fix null dereference

(cherry picked from commit d9a4906ac03be9f6ed3f3b45c56c866b867fd75b)