CVE-2026-64591: iommu/vt-d: Avoid WARNING in sva unbind path
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Avoid WARNING in sva unbind path
The Intel IOMMU driver allows SVA on devices even if they do not support PCI/PRI. Commit 39c20c4e83b9 ("iommu/vt-d: Only handle IOPF for SVA when PRI is supported") modified the SVA bind path to allow this configuration by skipping IOPF enablement when PRI is missing. However, it failed to update the unbind path.
This creates an imbalance: the unbind path attempts to disable IOPF for a device that never had it enabled, triggering a WARNING in inteliommudisableiopf():
WARNING: drivers/iommu/intel/iommu.c:3475 at inteliommudisableiopf+0x4f/0x90d Call Trace: <TASK> blockingdomainsetdevpasid+0x50/0x70 iommudetachdevicepasid+0x89/0xc0 iommusvaunbinddevice+0x73/0x150 xevmcloseandput+0x4d2/0x1200 [xe]
Fix this by bypassing IOPF operations for SVA domains on non-PRI hardware in both the bind and unbind paths.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-64591?
CVE-2026-64591 has a severity rating of 9, indicating a high level of risk.
How do I fix CVE-2026-64591?
To fix CVE-2026-64591, update your Linux kernel to the latest patched version that addresses this vulnerability.
What systems are affected by CVE-2026-64591?
CVE-2026-64591 affects systems using the Intel IOMMU driver in certain configurations of the Linux kernel.
What does CVE-2026-64591 specifically address?
CVE-2026-64591 addresses an issue where the Intel IOMMU driver improperly allows SVA on devices lacking PCI/PRI support.
Is there a workaround for CVE-2026-64591?
Currently, the recommended approach for CVE-2026-64591 is to apply the kernel update, as there are no known effective workarounds.