arch: arm: start threads on privileged stack
Use the privileged stack when starting K_USER threads in arch_new_thread().
Threads entering user mode with k_thread_user_mode_enter() keep their
existing flow. To support both cases, z_arm_userspace_enter() now takes an
internal ABI flag (sp_is_priv) indicating whether PSP already points to
the privileged stack.
Also fix calculation of the privileged stack top: use priv_stack_end
directly instead of priv_stack_start + CONFIG_PRIVILEGED_STACK_SIZE, which
failed to account for guard/FPU offsets applied to priv_stack_start.
Signed-off-by: Sudan Landge <sudan.landge@arm.com>
8 files changed
