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Did Elastic Cloud JTAG come out while I wasn't looking?

i think giving JTAG access on cloud machines may not be that a bad idea.

Connect as low-end sbb to server's JTAG output, and have it connected to the network. JTAG is beautiful tool for debugging because it requires no modification of software being debugged.

That would give the user full control over the physical CPU, though, whereas most "cloud" services only give you access to a virtual machine.

On the other hand, it should be possible for the hypervisor to provide roughly the same capabilities in software, without having to modify the software inside the virtual machine. Indeed, most hypervisors already provide a GDB stub for this purpose, including, e.g., Xen [1]; it's just that public clouds don't typically give customers access to it. It would be nice if that changed.

[1] https://github.com/xen-project/xen/tree/master/tools/debugge...

Somebody's cloud is engineered the wrong way if somebody can wreck the entirety of it when only having access to a single server

Usually the same physical server has multiple tenants, which do not trust each other.

i think it's called connecting a lauterbach or whatever to the server and giving remote access to the machine running the debugger. we just need a catchy name for it.

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