Executive brief
The Linux kernel's AMD GPU driver contains an unnecessary kernel panic (BUG_ON) in the GFX8 graphics pipeline that crashes the system for a condition that should be handled gracefully. This causes systems with affected AMD GPUs to experience kernel panics and service interruptions when the condition is triggered, even though the operation could safely continue without the panic.
Technical details
The vulnerability is a denial-of-service caused by an overly aggressive kernel panic (BUG_ON) in the DRM AMDGPU GFX8 driver's fence emission code (gfx_v8_0_ring_emit_fence_kiq function in drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c). The BUG_ON checks whether the AMDGPU_FENCE_FLAG_64BIT flag is set and crashes the kernel if true, even though this condition does not require a fatal system crash. The patch removes this unnecessary crash condition, allowing the kernel to continue operation. The fix is a simple code deletion requiring no replacement logic, affecting the AMD GPU driver used in systems with compatible hardware.
Affected products
- Linux Linux Kernel multiple stable branches from linux-4.x through linux-7.x
Timeline
- 2026-08-12: disclosed
- 2026-08-03: patched: patch applied to multiple stable kernel branches