A divide‑by‑zero error in the Linux kernel’s AMD display driver occurs when the calculate_mcache_setting function receives a plane with a zero‑area viewport. The function exits early with zero cache counts, leading to a subsequent division by zero that triggers a kernel panic or numeric underflow. This flaw results in an abrupt loss of service as the affected system crashes.

All Linux kernel builds that include the drm/amd/display driver and contain the unpatched calculate_mcache_setting routine are affected. Any kernel snapshot prior to the inclusion of commit 29c0f7c6, which introduces guards against zero‑dimension values, remains vulnerable, regardless of the specific distribution or kernel release.

Based on the description, it is inferred that an attacker must be able to configure a display plane with a zero‑area viewport, a capability normally limited to local users with kernel privileges or those who have already compromised the kernel via another vector. No remote attack surface is described. The CVSS score of 7.8 indicates high severity, while the EPSS score of less than 1% suggests a low probability of exploitation in the near term. The vulnerability is not listed in the CISA KEV catalog, further indicating it is not a currently known high‑profile target. Nonetheless, because the flaw can trigger a kernel panic, patching is strongly advised.