Documentation: Document array_index_nospec

Documentation: Document array_index_nospec

Document the rationale and usage of the new array_index_nospec() helper.

Signed-off-by: Mark Rutland <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Dan Williams <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: [email protected]
Cc: Jonathan Corbet <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: https://lkml.kernel.org/r/151727413645.33451.15878817161436755393.stgit@dwillia2-desk3.amr.corp.intel.com