CVE-2025-21644

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

drm/xe: Fix tlb invalidation when wedging

If GuC fails to load, the driver wedges, but in the process it tries to

do stuff that may not be initialized yet. This moves the

xe_gt_tlb_invalidation_init() to be done earlier: as its own doc says,

it's a software-only initialization and should had been named with the

_early() suffix.

Move it to be called by xe_gt_init_early(), so the locks and seqno are

initialized, avoiding a NULL ptr deref when wedging:

xe 0000:03:00.0: [drm] *ERROR* GT0: load failed: status: Reset = 0, BootROM = 0x50, UKernel = 0x00, MIA = 0x00, Auth = 0x01

xe 0000:03:00.0: [drm] *ERROR* GT0: firmware signature verification failed

xe 0000:03:00.0: [drm] *ERROR* CRITICAL: Xe has declared device 0000:03:00.0 as wedged.

...

BUG: kernel NULL pointer dereference, address: 0000000000000000

#PF: supervisor read access in kernel mode

#PF: error_code(0x0000) - not-present page

PGD 0 P4D 0

Oops: Oops:

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References