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Near and far JMP

I am collecting Linux, and I understand that it has a flat memory model. What I'm confused about is NEAR and FAR JMP.

NEAR is in one segment, and FAR is in another segment. As far as I understand, there are no segments in Linux virtual memory? Also, how do we know if my program code is laid out in several segments?

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For a long time he was not a segment. The correct term in x86 protected mode is a selector.

Having said that the difference between the near and far jump is that the former supports the same code selector cs, while the latter (usually) changes it.

In a flat memory model, the first case is almost always satisfied.

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