Red Hatters (and alumni) wear their Fedoras with pride

Here we are (again). Today is my last day at Red Hat for a second time. I leave behind several amazing teams spanning the gamut from Arm Architecture to Automotive and many things in between. I know that all of you are well positioned for success and although I will miss all of you, I also know that you will be fine without me. Keep doing awesome things dear friends :)

Red Hat is a special kind of place. There are few places where you can be surrounded by so many people who are passionate about Open Source. Red Hatters…


WARNING: mentions a patent that I was recently granted

At the end of 2020, I received notice that a patent application I filed almost a decade ago (back in 2011) had been issued, on “Automated cost assessment of cloud computing resources”. The idea I had back then was that the first player to commoditize a “unit of compute” and figure out how to do exchange trading (including futures trading) would have a hugely disruptive edge.

The idea that occurred to me more than a decade ago was that the public cloud is actually extremely early in its journey. Today, there…


A few days ago came the (not unexpected) news that Intel will have yet another new CEO, the third in three years, and the first in many years to come from an engineering background. This move represents a surprisingly good move for Intel as Pat is well regarded, and has a history leading microprocessor designs during his previous 30 years at Intel (prior to his leadership of VMWare).

In the semiconductor (and broader computing) industry, technical leadership is key. There is simply no alternative. You can’t financially engineer your way out of not having a solid technical grasp on the…


Today is my last day at NUVIA. It’s been a great experience working with Gerard, Manu, John, and the whole team of Nuvians who are well on the way toward disrupting the datacenter. I am particularly grateful to Gerard for giving me the opportunity to build and lead the NUVIA software organization in its early days. Although I won’t be there, we have built an incredible team of talented people who are going to continue to do amazing things long after I am gone. …


Author: Jon Masters, VP of Software, NUVIA

Standards are a key part of our everyday lives. From waking up in the morning, until we go to bed at night, we continually benefit from the interoperability that comes from being able to take certain things for granted. We couldn’t live our modern lives without the benefits that arise from being able to plug things together and have them “just work”. …


Fedora supports many different architectures, among them both the 64-bit, as well as the 32-bit Arm architectures. In Fedora, we call these by the names “aarch64” and “armv7hl” respectively. This post serves as a mini-writeup of a hard to debug problem with 32-bit builders, used to build packages, which in the case of Fedora run as guest virtual machines on 64-bit Armv8 hosts.

The Fedora Arm project began many years ago with efforts to support 32-bit generations of Arm hardware. In the early days, there were builds targeting the v5 32-bit architecture, then later this was replaced by the current…


8 years ago today, we started a little project to “ultimately support RHEL on ARM”. It started out as a skunkworks effort leveraging the great work that had already been started in the Fedora community around 32-bit Arm devices. 8 years later, we have a great story in both the Fedora and RHEL communities (and many other besides), and the future is strong. With the announcement of Amazon AWS A1 (Graviton) instances last fall, we enter a new phase in which the cloud adoption curve begins and Arm becomes mainstream.

Our goal was always to get to 64-bit as quickly…


I guess I can now admit to being at re:Invent in Las Vegas, and share a little bit about what I’ve been up to over the past little while. This is the first in a mini series, so stay tuned for more…

Today, Amazon announced their first Arm server offering. The new Amazon EC2 A1 instances provide a means for everyone to now share in the tremendous fun that is using and developing with Arm servers, which a few of us have been involved with for the past 8 years. I’ve been serving as technical lead on the Red Hat…


Modern microarchitectural attacks often depend upon data value speculation using values passed between contexts through general purpose registers (GPRs). A value is passed from one privilege level (e.g. userspace, EL0) into a kernel (EL1), or from one sub-context of the same privilege level (e.g. within a JIT runtime). In either case, the registers can be automatically tagged to identify the provenance of the value and track it through the microarchitecture implementation, and in particular the speculative backend.

Modern machines are implemented to provide a certain number of generally usable registers (GPRs). These are used for interim calculations, often as part…


[ This is going to be part of a much longer blog post, with diagrams, soon, consider this a draft that might be useful but is going to be pages long later, and I am possibly going to edit as I re-read and improve the language ]

Last week, the world learned more broadly about a class of hardware security vulnerability known as a “side channel attack”. …

Jon Masters

Computer Architect

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