Re: [PATCH v23 06/28] riscv/mm : ensure PROT_WRITE leads to VM_READ | VM_WRITE

[Andreas Schwab]

On Jun 01 2026, Deepak Gupta wrote:

> This was settled when x86 introduced shadow stack. Instead of having
> new `PROT_`, it was agreed to create a new syscall for mapping shadow
> stack memory (syscall: `map_shadow_stack`). Scenarios like `clone3` or
> co-routines required manufacturing a shadow stack, thus necessitating a
> new mechanism to create shadow stack style memory in demand. Instead
> of having a new PROT_ flag,  a new syscall was created.

So what prevents riscv from making use of VM_SHADOW_STACK similar as
x86, without the user visible effects?

-- 
Andreas Schwab, schwab@xxxxxxxxxxxxxx
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