Re: [PATCH 2/3] x86/entry: Rename the exception entrypoints

[Jan Beulich <jbeulich@xxxxxxxx>]

On 28.07.2023 21:43, Andrew Cooper wrote:
> This makes the names match the architectural short names that we use
> elsewhere.  This avoids 'debug' in particular from being a global symbol
> shadowed by many local parameter names.
> 
> Remove the DECLARE_TRAP_HANDLER{,_CONST}() infrastructure.  Only NMI/#MC are
> referenced externally (and NMI will cease to be soon, as part of adding FRED
> support).  Move the entrypoint declarations into the respective traps.c where
> they're used, rather than keeping them visible across ~all of Xen.

Coming back to my Misra concern here: There's no way we can avoid violating
rule 8.7 (and maybe also 8.6) when it comes to symbols defined in assembly
code. Rule 8.5 otoh is a little more relaxed than I recalled when commenting
on the earlier version of the patch, but it still talks of exclusively
"header files". Roberto, could you please clarify whether putting such
declarations in .c files is indeed not a violation of 8.5?

In any event I see you've added "nocall" - I guess that's an easy
identification for (some of) the symbols defined in assembly code, and
hence needing special casing in scans.

> Drop the long-stale comment at the top of init_idt_traps().  It's mostly
> discussing a 32bit Xen, and bogus otherwise as it's impossible to use trap
> gates correctly for these purposes.

I don't think I follow the "impossible", but I'm also not going to make my
(eventual) ack dependent upon you further adjusting this part of the
description.

Jan