Major upgrade! Intel CPU In-App Purchase (SDSI) has been added to the Linux 5.18 kernel

Recently, Phoronix reported that Hans de Goede, a Linux developer from Red Hat, revealed that if there are no surprises, Intel's mysterious "software-defined silicon (SDSi)" mechanism added to Xeon CPUs will be available in the upcoming Linux 5.18 kernel. officially supported.

It is reported that Intel Software Custom Silicon (SDSi) is a mechanism with the Pay-As-You-Go CPU Feature attribute that can be used to activate other additional features of server chips produced and deployed using the software (if an upgraded license is purchased license, these features are enabled after license activation).

At the same time, the SDSi driver also provides the ioctl interface for the corresponding socket for the application to perform the main configuration functions:

• Provides an Authentication Key Certificate (AKC), a key written to internal NVRAM that verifies the activation of a specific payload for a specific function.
• Provides the Activation Payload Capability (CAP), a token authenticated using the AKC that is applied to the CPU configuration to activate new capabilities.
• Read the SDSi status certificate, which contains the CPU configuration status.

In fact, as early as last September, Intel disclosed news about SDSi, which is characterized by the ability to activate locked chip functions through software, which can bring greater optimization to Linux systems running on Xeon Xeon CPUs.

This time, the Linux 5.18 version officially supports SDSi function, which also means that the upcoming Intel fourth-generation Xeon Xeon scalable processor Sapphire Rapids will become the first CPU to support SDSi.

For such a move by Intel, many people expressed "bewilderment". But for Intel, this decision is indeed very "sensible".

Reported that each generation of Intel Xeon Xeon CPU will add a lot of features, in order to make Intel's server platform more versatile.

For example, in addition to microarchitectural improvements and new instructions, Intel's Xeon Xeon Scalable CPUs (all generations) add support for up to 4.5TB of memory per socket, network function virtualization, speed selection technology, and large SGX enclave models, etc. In addition, there are optimized models for search, virtual machine density, infrastructure as a service (IaaS), software as a service (SaaS), liquid cooling, media processing, and more.

And with its 4th Gen Xeon Xeon Scalable "Sapphire Rapids" CPUs, Intel may be planning to add more specialized features for specific use cases (eg the SKU stack alone includes all types of different Xeon models).

If Intel chooses to earn a premium by offering workload-optimized SKUs, by disabling certain features on certain models, etc., the cost of doing so will be significant, and the large product lineup will cause a lot of confusion. .

So, Intel chose to make things easier by offering base models of Xeon Xeon Scalable CPUs, allowing customers to buy the extra features they needed, and enabling those features through software updates -- the SDSi mechanism.

At present, although Intel has not disclosed all the features of SDSi and the specific plan of the "pay-as-you-go CPU upgrade model" based on this mechanism, we can confirm that the Linux 5.18 version will provide formal support for SDSi functions and will support SDSi functions. Available this spring.

Therefore, we can guess more about Intel's move to add CPU in-app purchase (SDSI) to the Linux 5.18 kernel this time. If you also have related opinions on this topic, welcome to exchange and interact in the comment area.