I’m sure it was not. With specially prepared USB hardware you can read out main memory without any protection, and thus get around DRM. So they surely wanted to counter that.
You are right about USB, thunderbolt 3+PCI Express on the other hand allows very low level memory access, and in older implementations there’s nothing the operating system can do. But then again even if they force a specific thunderbolt configuration to prevent DMA it will still leave the “normal” PCIe ports as a way to access the memory outside the purview of the OS.
I’m sure it was not. With specially prepared USB hardware you can read out main memory without any protection, and thus get around DRM. So they surely wanted to counter that.
Source? Very skeptical that what you said can work without running anything on the system, which would be detectable on its own.
You are right about USB, thunderbolt 3+PCI Express on the other hand allows very low level memory access, and in older implementations there’s nothing the operating system can do. But then again even if they force a specific thunderbolt configuration to prevent DMA it will still leave the “normal” PCIe ports as a way to access the memory outside the purview of the OS.