CVE-2026-64100 addresses a deadlock in the Linux kernel drm/msm driver related to the shrinker mechanism. Under certain conditions on Snapdragon X1 hardware with PROVE_LOCKING enabled, a circular locking dependency arises between reservation_ww_class_acquire, reservation_ww_class_mutex, and fs_reclaim locks. This deadlock manifests during VM reclaim pressure when kswapd0 holds fs_reclaim and attempts to acquire the MSM shrinker lock, which in turn tries to reacquire fs_reclaim, causing a circular wait. The patch changes the locking strategy by using dma_resv_trylock() instead of dma_resv_lock(), dropping the wait-wound lock ticket to break the deadlock chain.

The vulnerability can cause kernel deadlocks during memory reclaim operations on affected hardware, potentially leading to system hangs or degraded performance. There is no indication of privilege escalation or code execution impact. The issue is specific to certain kernel configurations and hardware (Snapdragon X1 with PROVE_LOCKING).

A fix has been implemented in the Linux kernel to resolve this deadlock by modifying the locking mechanism in the drm/msm driver. Users should apply the official kernel update or patch that includes this fix. Since this is a kernel-level issue, upgrading to a kernel version containing the patch is the recommended remediation. Patch status is not explicitly confirmed in the provided data; check the vendor or kernel mailing list advisories for the exact fixed version and update accordingly.