Re: [PATCH v3 3/3] xen/riscv: introduce identity mapping

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

On Wed, 2023-07-19 at 13:38 +0200, Jan Beulich wrote:
> On 19.07.2023 12:39, Oleksii wrote:
> > On Tue, 2023-07-18 at 17:03 +0200, Jan Beulich wrote:
> > > On 17.07.2023 16:40, Oleksii Kurochko wrote:
> > > > @@ -35,8 +41,10 @@ unsigned long __ro_after_init phys_offset;
> > > >   *
> > > >   * It might be needed one more page table in case when Xen
> > > > load
> > > > address
> > > >   * isn't 2 MB aligned.
> > > > + *
> > > > + * CONFIG_PAGING_LEVELS page tables are needed for identity
> > > > mapping.
> > > >   */
> > > > -#define PGTBL_INITIAL_COUNT ((CONFIG_PAGING_LEVELS - 1) + 1)
> > > > +#define PGTBL_INITIAL_COUNT (CONFIG_PAGING_LEVELS * 2 + 1)
> > > 
> > > Where did the "- 1" go?
> > My fault. Should be:
> >   #define PGTBL_INITIAL_COUNT ((CONFIG_PAGING_LEVELS * 2  - 1) + 1)
> 
> Why? I'd have expected
> 
> #define PGTBL_INITIAL_COUNT ((CONFIG_PAGING_LEVELS - 1) * 2 + 1)
> 
I confused myself with definition of PGTBL_INITIAL_COUNT from another
branch so your option is correct.
Thanks.

~ Oleksii