Re: [PATCH 06/17] xen/x86: mm: Fix the comment on top put_page_from_l2e() to use 'mfn'

[Julien Grall <julien@xxxxxxx>]

Hi Jan,

On 26/03/2020 15:51, Jan Beulich wrote:
> On 22.03.2020 17:14, julien@xxxxxxx wrote:
> > From: Julien Grall <jgrall@xxxxxxxxxx>
> >
> > We are using the 'mfn' to refer to machine frame. As this function deal
> > with 'mfn', replace 'pfn' with 'mfn'.
> >
> > Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx>
> >
> > ---
> >
> > I am not entirely sure to understand the comment on top of the
> > function, so this change may be wrong.
> Looking at the history of the function, ...
>
> > --- a/xen/arch/x86/mm.c
> > +++ b/xen/arch/x86/mm.c
> > @@ -1321,7 +1321,7 @@ static int put_data_pages(struct page_info *page, bool 
> > writeable, int pt_shift)
> >   }
> >   
> >   /*
> > - * NB. Virtual address 'l2e' maps to a machine address within frame 'pfn'.
> > + * NB. Virtual address 'l2e' maps to a machine address within frame 'mfn'.
> >    * Note also that this automatically deals correctly with linear p.t.'s.
> >    */
> >   static int put_page_from_l2e(l2_pgentry_t l2e, mfn_t l2mfn, unsigned int 
> > flags)
> ... it used to be
>
> static int put_page_from_l2e(l2_pgentry_t l2e, unsigned long pfn)
>
> When the rename occurred (in the context of or as a follow-up to an
> XSA iirc), the comment adjustment was apparently missed. With the
> referenced name matching that of the function argument (l2mfn)
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
I will update the reference to use 'l2mfn' and also add a word that the 
comment was adjusted in ea51977a7aa5e645680a7194550fbceb59004ccf.
Cheers,

--
Julien Grall