On Tue, Jun 19, 2018 at 02:15:24PM +0100, Mark Rutland wrote:

On Tue, Jun 19, 2018 at 01:18:17PM +0100, Dave Martin wrote:

quoted

On Mon, Jun 18, 2018 at 01:03:01PM +0100, Mark Rutland wrote:

quoted

+static inline void sve_user_reset(void)
+{

Can we call this "sve_user_discard" please?

"Reset" is a reasonable name for the concept, but the "discard"
terminology has been used elsewhere.

Sure; done.

quoted

quoted

+	if (!system_supports_sve())
+		return;
+
+	/*
+	 * task_fpsimd_load() won't be called to update CPACR_EL1 in
+	 * ret_to_user unless TIF_FOREIGN_FPSTATE is still set, which only
+	 * happens if a context switch or kernel_neon_begin() or context
+	 * modification (sigreturn, ptrace) intervenes.
+	 * So, ensure that CPACR_EL1 is already correct for the fast-path case.
+	 */

This comment should go after clear_thead_flag(), since it describes not
the purpose of this function but the presence of sve_user_disable().

quoted

+	clear_thread_flag(TIF_SVE);
+	sve_user_disable();
+}

Good point. I've moved the clear_thread_flag(TIF_SVE) above the comment
(with a blank line before the comment).

Thanks -- with those changes:

Reviewed-by: Dave Martin <Dave.Martin@arm.com> (for the SVE parts)

Cheers
---Dave