Re: [PATCH v4 15/30] riscv/mm: Implement map_shadow_stack() syscall

On Thu, Sep 12, 2024 at 04:16:34PM -0700, Deepak Gupta wrote:

This patch implements this syscall for riscv. riscv doesn't require token to be setup by kernel because user mode can do that by itself. However to provide compatibility and portability with other architectues, user mode can specify token set flag.

The arm64 series also adds SHADOW_STACK_SET_MARKER for a top of stack marker, if this is only being done for compatibility it might be good to pick that up as well. I don't know what the thoughts are on using them for RISC-V. On arm64 the top of stack marker is just all bits 0.