Re: Proposal: Delegating Exceptions from VS-mode or VU-mode to U-mode
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The N extension is effectively deprecated. We don’t see sufficient demand for user-level interrupts in managed/Unix-like environments to pursue that approach at this time.
We do see demand for this feature in embedded systems with two levels of privilege. In this case, the proposal is to run the trusted piece in M-mode and the less-trusted piece in “bare S-mode”: i.e., S-mode without virtual memory.
This approach covers the interesting use cases without additional architectural complication, and in particular, the hypervisor architecture need not care.
On Fri, Sep 18, 2020 at 1:03 AM Yifei Jiang via lists.riscv.org <jiangyifei=huawei.com@...> wrote: