CVE-2026-90243: In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Clear Present bit before tearing down c

A vulnerability in the Linux kernel's Intel IOMMU (input/output memory management unit, which controls how devices access system memory) driver could allow hardware to fetch incomplete data because the Present bit (a flag indicating valid data) wasn't cleared before erasing a context entry. This timing gap could cause unpredictable behavior or false errors because the hardware might read partially zeroed data while the entry still appears valid.