Re: arch/x86/lib/copy_mc.c:30:1: warning: no previous prototype for 'copy_mc_fragile_handle_tail'

From: Dan Williams
Date: Wed Jun 09 2021 - 20:13:45 EST


On Wed, Jun 9, 2021 at 4:55 PM Luck, Tony <tony.luck@xxxxxxxxx> wrote:
>
> > This routine is only ever called from ASM code, so the fact that there
> > is no C declaration is expected.
>
> Does the asm code really need to call back into C?
>
> Could you just have the asm code do "jmp .L_read_trailing_bytes" (might need to only do that if %ecx is non-zero)?

I could... it turns out when Peter did this:

3693ca81151e x86/uaccess: Move copy_user_handle_tail() into asm

...he did not also go fixup my cargo culting. I'll take a look...