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so i think running linux on your hard drive is a totally awesome hack but it's hard not for the reason people would expect for an OS kernel, linux is surprisingly self-contained. it needs barely any hardware or CPU support to run twitter.com/Theophite/stat

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Catherine

@whitequark

Oct 4, 2020

the hard part is usually the reverse engineering of the completely black box target, plus (for me at least) the added psychological complication of it being unclear whether it can support my goals at all actually running linux on it tends to be straightforward

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Catherine

@whitequark

Oct 4, 2020

to get a shell running you'll need a few privileged instructions, a working MMU, an UART, and that's just about it. while it is hard to figure out what your target is and how to safely run a large binary on it, it's not that hard to get this small number of requirements working

Catherine

@whitequark

Oct 4, 2020

on the flipside, since the port of linux to your hard drive, or toaster, or Casio BE-300 doesn't require much for a proof of concept, people tend to get it to the point where a shell runs and stop working on it. if it has buttons you get buttons, not applicable to hard drives tho

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it does fucking what

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The Pixel Visual Core on a Pixel 2 and 3 runs a Linux distribution uploaded by the OS. It was an Intel-built chip with an ARM core running Linux and managing the specialized hardware. twitter.com/kdrag0n/status Not sure if it's also the case with the Pixel Neural Core on Pixel 4.

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Danny Lin

@kdrag0n

Jul 9, 2020

Mainline Linux v5.8-rc4 kernel running on a Pixel Visual Core image coprocessor, built with Clang 11 + LTO + CFI + SCS for kicks. It runs Linux, so why not put it to good use? github.com/kdrag0n/mainli

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Not entirely related, but modern Qualcomm SoC smartphones also mostly don't have dedicated Wi-Fi hardware anymore. Wi-Fi and Bluetooth run as sandboxed processes on the baseband RTOS. 95% of the complexity of the Wi-Fi stack is implemented in a massive qcacld Linux kernel driver.

10:45 PM · Oct 4, 2020Twitter Web App

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I wouldn't be surprised if the qcacld codebase was at least initially shared with their Wi-Fi firmware. It's very abstracted and hardly looks like Linux kernel driver code at all. They took the firmware and put it into the Linux kernel instead of having much firmware anymore.