Linux 4.6 Will Try To Make It Easier To Find Assembly Code Bugs

[Ardje]

But locks probably only need atomics, which are standardised in C11.

(kernel) Atomics are cpu architecture specifics, which probably are implemented in assembly anyway. It can involve cache invalidation, buslocks or other constructs, and usually they are implemented using (spin)locks and turning of irq's.

[Ardje]

I honestly don't even know what all that ASM does. I mean, the only things that come to mind for me are boot sequence, interrupt preamble/register saving, and page table remapping/TLB invalidation, all of which are architecture-dependent.

Crypto and raid calculations come to mind.
There is not a lot of assembly in the kernel. But that what's in the kernel usually has a reason to be there and from time to time gets re-evaluated.
Just like the routing cache has been re-evaluated and thrown out because it caused more problems and used more resources than the very tiny amount of speed increase waranted.
And yes, it's all architecture dependent, because that's the nature of assembly ;-).