CVE-2026-43253

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description When iommu.strict is set to 1, the completion wait path can cause soft lockups in stressed environments. This occurs because the wait on sem() function busy-waits while holding a spinlock with interrupts disabled. The wait on sem() function only polls the hardware-updated cmd sem and does not require the iommu->lock, meaning holding the lock during this process unnecessarily increases contention and extends the duration that interrupts remain disabled. The issue is addressed by moving the completion wait in the iommu completion wait() function outside of the spinlock.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.