On Tue, Sep 03, 2024 at 08:57:20PM +0100, Mark Brown wrote:
On Tue, Sep 03, 2024 at 03:41:49PM -0400, Liam R. Howlett wrote:
* Mark Brown <broonie@xxxxxxxxxx> [240902 15:09]:
> +static inline unsigned long stack_guard_placement(vm_flags_t vm_flags)
> +{
> + if (vm_flags & VM_SHADOW_STACK)
> + return PAGE_SIZE;
Is PAGE_SIZE is enough?
It's what x86 currently uses so it'll be no worse off if it gets moved
to the generic code (there's a comment in the arch code explaing what's
needed there) and it's enough for arm64, we only do single record
pushes/pops or (optionally) writes to unconstrained addresses.
It's enough for RISC-V too.
