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Comment by sudo-i | Hacker News Reader

Does this have any bearing on running linux on macbooks?

> Does this have any bearing on running linux on macbooks

Unlike on PCs, on T2 Macs Linux will only be bootable with Secure boot disabled making the system much less secure.

To make matters worse, the T2 chip administers access to the built in SSD, so it will be completely inaccessible for Linux to use for anything.

When Apple stops supporting this machine, you won’t be able to keep it chugging by loading another OS.

I could say Apple is trying to terminate the only remaining computing platform which respects end-user freedom and ownership, but I’m not sure if it would be a joke or not...

> the T2 chip administers access to the built in SSD, so it will be completely inaccessible for Linux to use for anything.

This isn’t true. You can install Linux on this, providing you disable Secure Boot. You can’t currently access the SSD, but that’s more the result of a driver not existing than it being inherently disallowed.

> You can’t currently access the SSD, but that’s more the result of a driver not existing than it being inherently disallowed.

That's not clear yet. There is a NVMe driver available in Linux which works fine with pre-T2 Macs. On T2 Macs however the whole platform resets a few seconds after initializing the NVMe controller. The question is: Is that a bug in the driver or NVMe implementation of the T2 chip or something Apple does intentionally?

I can envision a scenario where T2, when booted with Secure Boot disabled, tries to protect a Secure Boot OS and user data stored on the internal mass storage device in the event of the user subsequently re-enabling Secure Boot thus adding a layer of guarantee that everything is safe even during the time window when Secure Boot was disabled.

If intentional, this behaviour is nonetheless not documented in the whitepaper.

In such a scenario, a possible solution could be to offer an option to force an internal disk erasure upon toggling secure boot, in which case the internal device would be cleared for non-secure OS access.

That's interesting; I was not aware of the exact circumstances around why this driver didn't exist. Do you know where I could look to find more detail on the state of development for this?

Let's not attribute to malice what can easily be attributed to incompetence.

In a chip that has "secure" in its name, it's quite likely that a sudden system shutdown is intentional..

AFAIK, there's no way to inject new keys, so you have a exclusive choice between running Linux and having secure boot enabled.

So it doesn't stop you in a way a game console might, but you lose some features of the hardware by doing so.

Even with secure boot disabled you can't install Linux on the internal SSD. Installing Linux on a Mac has already been very flaky for the last few years, but now is impossible.

https://unix.stackexchange.com/questions/463422/how-can-you-...

Interesting that Windows 10 installed via Boot Camp is an allowable exception, but Linux is not.

I wonder if Apple have an official stance on that.. i.e. "we're working on it", or "never".

This is because Apple has included the keys for Windows, but has not added the Microsoft UEFI key for Linux.

The likely problem is a lack of driver support for using the T2 as an SSD controller. I don’t think, based on Apple’s white paper, that they did anything to explicitly block Linux from accessing the internal SSD - it just needs to go through the T2 for that.

Hopefully someone is working on the necessary driver support - these laptops are still very new so maybe nobody has gotten around to it yet.

Apple is actively blocking unsigned software from accessing the internal storage as a security measure and providing no means to add allowed keys. Its possible there is a defect in this security that could be exploited but it would be explicitly a bug and would be liable to be patched in the next version of the software. You have completely misread the situation. This is apple taking over your machine while still expecting you to pay for it.

Not if you disable secure boot. Imo they're probably right about Linux not being able to talk to T2. We'll see about that, I guess.

Yes, the issue is that Linux doesn’t know how to talk to the SSD, not Apple stopping Linux from accessing the SSD.

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