CVE-2025-40329

A deadlock flaw was found in the Linux kernel's DRM GPU scheduler. In drm_sched_entity_kill_jobs_cb(), improper locking order between the xarray lock (xa_lock) and fence lock can cause a deadlock. When CPU0 holds xa_lock and an interrupt triggers on CPU1 that requires both fence->lock and xa_lock, the system deadlocks. Additionally, if two fences share the same spinlock, calling dma_fence_add_callback() from within dma_fence_signal() creates another deadlock scenario. A local user with access to GPU resources could trigger this condition, causing a system hang.

This vulnerability affects systems with DRM-based GPU drivers that use the kernel's GPU scheduler. Exploitation requires local access and the ability to submit GPU workloads. The deadlock results in a denial of service requiring a system reboot to recover.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.