Linux i915 GPU kernel driver (GTT TLB handling): Stale GPU TLB entries let the GPU keep reading physical pages after

Impact

Stale GPU TLB entries let the GPU keep reading physical pages after they were unmapped and handed to somebody else. A tenant running crafted GPU code reads whatever the host recycled those pages into - other tenants' data, or kernel memory. This is a true cross-tenant memory disclosure on Intel GPU nodes, not a crash bug.

Who can reach it

Any local user or container with a DRM render node - i.e. any tenant that was scheduled a GPU. No privileged capability needed.

What to do

Update the kernel and reboot; the fix forces a full TLB flush on unbind, which costs GPU unbind throughput on memory-churning workloads. Drain the node - the driver cannot be swapped under live GPU jobs. Kernel-only, no firmware or microcode.

References