Linux 6.12 will support permission override extensions from Arm

64-bit ARM changes have been submitted early to the now-open Linux 6.12 kernel merge window. This cycle, Arm also has work to do in terms of confidential computing and other new capabilities. After a year of kernel development, ArmPermissionOverlayExtension support finally appeared in Linux 6.12.

Arm’s permission coverage extensions were added to the ArmA-Profile specification in 2022. PermissionOverlayExtension provides the ability to restrict memory area permissions and can be used in user space. With support for this extension, it can be used to implement Linux memory protection key system call support.

In terms of Arm confidential computing, Linux 6.12 adds support for launching the ARM64 kernel as a protected guest under Android's protected KVM "pKVM" hypervisor.

Other ARM64 changes for Linux 6.12 include errata workarounds for HiSilicon and AmpereOne platforms, crash fixes for the AMDGPU driver on AMD64, and various other fixes.

For more details on the Linux 6.12 ARM64 architecture changes, please see the pull request.