Re: [PATCH v3 10/20] xen/riscv: introduce page_{get,set}_xenheap_gfn()

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 8/5/25 4:11 PM, Jan Beulich wrote:

> On 31.07.2025 17:58, Oleksii Kurochko wrote:
> > --- a/xen/arch/riscv/include/asm/mm.h
> > +++ b/xen/arch/riscv/include/asm/mm.h
> > @@ -12,6 +12,7 @@
> >  #include <xen/sections.h>
> >  #include <xen/types.h>
> >  
> > +#include <asm/cmpxchg.h>
> >  #include <asm/page.h>
> >  #include <asm/page-bits.h>
> >  
> > @@ -247,9 +248,17 @@ static inline bool arch_mfns_in_directmap(unsigned long mfn, unsigned long nr)
> >  #define PGT_writable_page PG_mask(1, 1)  /* has writable mappings?         */
> >  #define PGT_type_mask     PG_mask(1, 1)  /* Bits 31 or 63.                 */
> >  
> > -/* Count of uses of this frame as its current type. */
> > -#define PGT_count_width   PG_shift(2)
> > -#define PGT_count_mask    ((1UL << PGT_count_width) - 1)
> > + /* 9-bit count of uses of this frame as its current type. */
> >       
> Nit: Stray blank at start of line.
>
> > +#define PGT_count_mask    PG_mask(0x3FF, 10)
> >       
> A 9-bit count corresponds to a mask of 0x1ff, doesn't it? With 0x3ff the count
> can spill over the type.
>     
It should be really 0x1ff, thanks.

~ Oleksii