[rollcat]

Firmware is not OS.

Your machine is a distributed system. The firmware is what runs a specific node.

Yes they usually have DMA, shared busses, etc. That's an implementation detail.

[fragmede]

An implementation detail where TLAs could theoretically get root remotely? Seems like a bit more than a detail to be glossed over.

[rollcat]

Free firmware can have a security issue and root your device.

A working IOMMU will stop both free- and non-feee firmware from rooting your device.

These concepts are orthogonal.