How userstart affect Virtual Addressing in riscv tests?

[iamazizhaider]

Can you guide me about this userstart that the we set in Virtual environment.

When I run on spike, this sets the sepc register causing system to go into "exception trap_instruction_page_fault, epc 0x0000000000001aa4". The very next instruction takes us into VA space. I am unable to understand this behaviour.

This image is from riscv-tests/env/v/entry.S

We basically load userstart address into a0 and load sepc from a0. That sepc is 0x1aa4 and how does it change to 0x780001aa4 when I change the memory map to 0x800000000 instead of 0x80000000. The userstart I got from dump is this (coudln't find source file)

I am fairly new to this so would appreciate any help I can get to make it running on my own software emulator that requires addressing space of 0x800000000.