Comment by qiqitori
10 months ago
"we were still stuck without DP Alt Mode (a feature which required deep reverse engineering, debugging, and kernel surgery to pull off, and which, if it were to be implemented properly and robustly, would require a major refactor of certain kernel subsystems or perhaps even the introduction of an entirely new subsystem)."
Few maintainers care about the platform in question (to whom it's more a curiosity like maybe 68k), and don't have the hardware to test any submitted patches. It's painful to have to accept code that you can't test (though it may be common in certain parts of the kernel). It's painful to see a bunch of changes for just one random feature on a random platform. It's unclear how the code will affect other platforms, etc.
Now throw in some controversial stuff. The vendor of the platform is Apple and some patches are written in Rust... oh em gee!
Are you saying that PCs do not usually have the ability to plug into a monitor, to charge, and to connect to a USB hub for the rest of your devices from a single USB-C port?
You guys still plug three cables each time you sit at a desk?
My Linux laptop can charge, provide USB ports, connect to my monitor and provide Ethernet connectivity from a single cable.
This laptop came out 7 years ago, but I'm sure much older models can do this just fine too.
The problem is that Apple does DP Alt mode in a different way top everyone else, which apparently requires a large amount of changes to the kernel
When was the last time you touched a PC, 2003? They most certainly do, when the OEM actually supports it: https://www.kernel.org/doc/html/latest/admin-guide/thunderbo...
It's not ever coming to Apple Silicon on Linux since post-Thunderspy, Thunderbolt is dangerous to implement even in the best of circumstances. You'd have to reverse-engineer and update Apple's IOMMU, write software drivers for the port since it doesn't have firmware and test it across a variety of vulnerable devices to see how secure it is.
> when the OEM actually supports it
that sentence carries a lot of weight. How many millions of users are left in the dust? Last time I touched a PC, the USB-C port could charge the laptop, unless the battery was empty. Then only the barrel plug could be used. It. was. infuriating.
1 reply →
> Few maintainers care about the platform in question (to whom it's more a curiosity [...]) and don't have the hardware to test any submitted patches.
Yeah, from some very brief research I could only find a singular Linux kernel developer/maintainer/creator who said[0] "I'd absolutely love to have [the new 2020 Air], if it just ran Linux".
Who knows if that one person has even used Apple hardware before or has access to the necessary hardware to put toward a practical use such as a "development platform" while travelling, or, "doing test builds and boots and now the actual [Linux kernel] release tagging"[1][2], let alone be supportive of experimenting with Rust in the Linux kernel[3].
The history of Linux demonstrates the project doesn't have the resources to go chasing support for a hardware platform just because Linus cares about the platform in question...
...even if at least "173 people, and many more" "contributed both to the Linux kernel side but also to the upstream Rust side to support the kernel's needs" in the initial merge[3].
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[0] https://www.realworldtech.com/forum/?threadid=196533&curpost...
[1] https://lore.kernel.org/lkml/CAHk-=wgrz5BBk=rCz7W28Fj_o02s0X...
[2] via: https://arstechnica.com/gadgets/2022/08/linus-torvalds-uses-...
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...