Linus Torvalds releases Linux 5.19 – using Asahi on an Arm-powered Mac

Linus Torvalds has released version 5.19 of the project, and hailed Apple's homebrew silicon – and the Asahi Linux distribution that runs on it – for making Arm-powered computers useful for developers.

In his announcement of the release, Torvalds called out work to support for the made-in-China Loongarch RISC architecture as an important step, along with "another batch of the networking sysctl READ_ONCE() annotations to make some of the data race checker code happy."

Torvalds then revealed he's got his hands on some Apple silicon.

"On a personal note, the most interesting part here is that I did the release (and am writing this) on an arm64 laptop. It's something I've been waiting for for a _loong_ time, and its finally reality, thanks to the Asahi team," he wrote. "We've had arm64 hardware around running Linux for a long time, but none of it has really been usable as a development platform until now."

The emperor penguin hedged a little, admitting "Not that I've used it for any real work, I literally have only been doing test builds and boots and now the actual release tagging."

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But it appears Torvalds wants an Apple-powered Mac to become his go-to machine when he’s on the road.

"I'm trying to make sure that the next time I travel, I can travel with this as a laptop and finally dogfooding the arm64 side too."

"It's the third time I'm using Apple hardware for Linux development – I did it many years ago for PowerPC development on a ppc970 machine," he wrote. "And then a decade+ ago when the MacBook Air was the only real thin-and-lite around. And now as an arm64 platform."

Among the headline features of version 5.19 of the kernel:

• Support for Intel's Trust Domain Extensions that isolate virtual machines from the virtual-machine manager/hypervisor and any other software on the platform, to add isolation beyond that achievable with conventional virtualization;
• Support for AMD's SEV-SNP, which protects VMs against attacks on the hypervisor;
• Multiplatform support for Arm is pretty much done;
• Improved monitoring of ASUS motherboards;
• Removal of support for Renesas's H8/300 CPU architecture, which has the odd distinction of already having been removed from the kernel, then reinstated.

The fine folk at Phoronix have an extensive list of what's new in 5.19.

Torvalds's post ends with a footnote in which he states he intends to call the next release of the kernel version 6.0 "since I'm starting to worry about getting confused by big numbers again."

That's slightly inconsistent with the 4.x series, which reached version 4.20, but follows the same scheme used on the 3.x series which stopped at 3.19.

None of which makes a real difference anyway, because there is no indication the next kernel will offer the kind of step-change in functionality that would justify a x.0 release in either open source or commercial software. ®