Ah, that explains this patchset that was submitted to the Linux kernel today

"KVM: s390: Introduce arm64 KVM"

"By introducing a novel virtualization acceleration for the ARM architecture on s390 architecture, we aim to expand the platform's software ecosystem. This initial patch series lays the groundwork by enabling KVM-accelerated ARM CPU virtualization on s390....."

https://patchwork.kernel.org/project/linux-arm-kernel/cover/...

This is a serious question. What does IBM, in fact, do? I'm surprised they are still around and apparently relevant. Are they more or less a services and consulting company now?

> dual‑architecture hardware that helps enterprises run future AI and data intensive workloads with greater flexibility, reliability, and security

I think we can ignore the "AI" word here as its presence is only because everything currently has to be AI.

So why would IBM add ARM?

> As enterprises scale AI and modernize their infrastructure, the breadth of the Arm software ecosystem is enabling these workloads to run across a broader range of environments

I think it has become too expensive for IBM to develop their own CPU architecture and that ARM64 is starting to catch up in performance for a much lower price.

So IBM wants to switch to ARM without making a too big fuzz about it.

Once you parse the marketing speak, looks like there may be ARM ISA silicon in future System Z.

But, what are their legacy finance-sector customers asking for here? Are they trying to add ARM to LinuxONE, while maintaining the IBM hardware-based nine nines uptime strategy/sweet support contract paradigm?

If so, why don't the Visas of the world just buy 0xide, for example?

> develop new dual‑architecture hardware that helps enterprises run future AI and data intensive workloads with greater flexibility, reliability, and security.

> "This moment marks the latest step in our innovation journey for future generations of our IBM Z and LinuxONE systems, reinforcing our end-to-end system design as a powerful advantage."

I think the #1 use case here is allowing AI/cloud workloads the ability to execute against the mainframe's data without ever leaving the secure bubble. I.e., bring the applications to the data rather than the data to the applications.

IBM could put an entire 1k core ARM mini-cloud inside a Z series configuration and it could easily be missed upon visual inspection. Imagine being able to run banking apps with direct synchronous SQL access to core and callbacks for things like real-time fraud detection. Today, you'd have to do this with networked access into another machine or a partner's cloud which kills a lot of use cases.

If I were IBM, I would set up some kind of platform/framework/marketplace where B2B vendors publish ARM-based apps that can run on Z. Apple has already demonstrated that we can make this sort of thing work quite well with regard to security and how locked down everything can be.

I wonder if we end up with z series running on arm long term.

The value in z series is in the system design and ecosystem, IBM could engineer an architecture migration to custom CPUs based on ARM cores. They would still be mainframe processors, but likely able to be able to reduce investment in silicon and supporting software.

It is wild how ARM - which was kind of a niche company and ISA - has taken the world by storm since the modern smartphone was born. Now their designs make their way upwards to big iron and AI datacenters.

Maybe I don't know enough technical details about these CPU architectures or IP agreements, but I don't see why IBM couldn't have done what Arm did but with PowerPC.

2026 continues to amaze me.

I never would have expected such, but now I'm getting used to it.

I'm waiting for Apple and Microsoft to announce collaboration. They probably already do, but Apple knows its bad for marketing.

I'm not sure I can be surprised anymore.

IBM is desperate to keep the mainframe relevant. The typical transactional workloads are going to stay on the mainframe, and by bolting on ARM “for AI”they’re giving their customer CIOs a reason to defend their decision to stick with the mainframe.

I miss working on Power platforms. It is such a nice system with openfirmware. The world went another way.

Nvidia tried, it’s IBM turn now

Arm co processors for main frames?

AIX for ARM? ;-)

I wonder how this relates to Linaro, a joint venture of ARM, IBM, and others started in 2010.

https://en.wikipedia.org/wiki/Linaro

[dead]

TLDR; “fine, we’ll support Arm too because customers want it.”

Is that good or bad?

My gut feeling says to lean more on the bad side. I am very skeptic when corporations announce "this is for the win". Then I slowly walk over to the Google Graveyard and nod my head wisely in sadness ... https://killedbygoogle.com/

great

IBM and 'track record of innovation' ... is a bit of an understatement.

April fools day was yesterday, IBM.

Arm is trying to expend it's horizons every where as in the previous year ARM acquired the Arduino.