Imagination Announces The PowerVR Series8XT GT8540 GPU

[starshipeleven]

But no, car makers wanted to let people control suspension from the big touchscreen instead of placing extra buttons somewhere.

It's just cost-cutting or they don't believe the risks are real because they have the same mindset they had when the cars were not basically a smartphone with wheels, so they could get away with any crap because there was no remote access anyway.

Technically speaking, you can still have the big touchscreen control that without attaching the whole thing to CANbus (the internal network of the car) and without having major security issues.

It's called "mailbox registers", basically two physically separated systems exchange a variable containing bits (on/off switches) or variables (values) and it's widely employed in embedded https://msreekan.com/tag/mailbox/ It can be done at any level, either hardware or using a dedicated ethernet connection or something.

[chithanh]

Now that it is there, the communications channel will be used to pass more complex (ie. variable length at least) data, requiring nontrivial parsers at the other end. So almost nothing gained.

With vc4 mailbox registers, I think even function pointers are passed.

[starshipeleven]

Now that it is there, the communications channel will be used to pass more complex (ie. variable length at least) data, requiring nontrivial parsers at the other end. So almost nothing gained.

With vc4 mailbox registers, I think even function pointers are passed.

No, my point is that to have buttons on a screen on the media center system doing something to the otherwise isolated car mainboard you don't need to pass anything remotely complex to do all it can realistically need to do.

Each button is a bit that can be 1 or 0, and some numerical values (for sensors or configurations) can be passed around the same way. You just assemble them as a single raw binary number and write them in a mailbox register (or similar). What else does the media system actually needs to exchange with the mainboard?

Parsing this is a joke. First bit is button A (two states= 1 pressed, 0 not pressed), second bit is button B, third-fifth bits are value X, and so on. And there is no way in hell that malware can send any kind of executable code through this. Industrial automation uses this system all the time to pass information around, so it's not my own genial idea or something.

There is no need to pass raw function pointers or anything like that, not to mention that in Raspi both CPU and GPU have access to the same RAM so you can pass pointers fine, while in a car system the mainboard and the media center would not be sharing RAM at all, so yeah, there is no reason to pass pointers.