Hi all,

On Thu, 4 Jun 2020 16:52:46 +1000 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
> index c188a6f64bcd..1927e1b653f2 100644
> --- a/arch/powerpc/include/asm/nohash/32/pgtable.h
> +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
> @@ -205,10 +205,6 @@ static inline void pmd_clear(pmd_t *pmdp)
>  	*pmdp = __pmd(0);
>  }
>  
> -
> -/* to find an entry in a kernel page-table-directory */
> -#define pgd_offset_k(address) pgd_offset(&init_mm, address)
> -
>  /* to find an entry in a page-table-directory */
>  #define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
>  #define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
> @@ -241,7 +237,7 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p
>  	pte_basic_t old = pte_val(*p);
>  	pte_basic_t new = (old & ~(pte_basic_t)clr) | set;
>  	int num, i;
> -	pmd_t *pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
> +	pmd_t *pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr);
>  
>  	if (!huge)
>  		num = PAGE_SIZE / SZ_4K;
> @@ -341,6 +337,10 @@ static inline int pte_young(pte_t pte)
>  	pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
>  #endif
>  
> +#define pte_offset_kernel(dir, addr)	\
> +	(pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \
> +				  pte_index(addr))
> +
>  /*
>   * Encode and decode a swap entry.
>   * Note that the bits we use in a PTE for representing a swap entry

Sorry, that ended up:

diff --cc arch/powerpc/include/asm/nohash/32/pgtable.h
index 639f3b3713ec,eb8538c85077..1927e1b653f2
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@@ -204,13 -205,6 +205,9 @@@ static inline void pmd_clear(pmd_t *pmd
  	*pmdp = __pmd(0);
  }
  
- 
- /* to find an entry in a kernel page-table-directory */
- #define pgd_offset_k(address) pgd_offset(&init_mm, address)
- 
 +/* to find an entry in a page-table-directory */
 +#define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
 +#define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
  
  /*
   * PTE updates. This function is called whenever an existing
@@@ -240,7 -234,7 +237,7 @@@ static inline pte_basic_t pte_update(st
  	pte_basic_t old = pte_val(*p);
  	pte_basic_t new = (old & ~(pte_basic_t)clr) | set;
  	int num, i;
--	pmd_t *pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
++	pmd_t *pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr);
  
  	if (!huge)
  		num = PAGE_SIZE / SZ_4K;
@@@ -342,15 -334,6 +337,10 @@@ static inline int pte_young(pte_t pte
  	pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
  #endif
  
- /* Find an entry in the third-level page table.. */
- #define pte_index(address)		\
- 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 +#define pte_offset_kernel(dir, addr)	\
 +	(pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \
 +				  pte_index(addr))
- #define pte_offset_map(dir, addr)	pte_offset_kernel((dir), (addr))
- static inline void pte_unmap(pte_t *pte) { }
 +
  /*
   * Encode and decode a swap entry.
   * Note that the bits we use in a PTE for representing a swap entry

-- 
Cheers,
Stephen Rothwell