On Thu, Jun 04, 2020 at 09:44:46AM +0200, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> The pud_alloc_track() needs to do different checks based on whether
> __ARCH_HAS_5LEVEL_HACK is defined, like it already does in
> pud_alloc(). Otherwise it causes boot failures on PowerPC.
>
> Provide the correct implementations for both possible settings of
> __ARCH_HAS_5LEVEL_HACK to fix the boot problems.
>
> Reported-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
> Tested-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
> Tested-by: Satheesh Rajendran <sathnaga@xxxxxxxxxxxxxxxxxx>
> Fixes: d8626138009b ("mm: add functions to track page directory modifications")
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> include/asm-generic/5level-fixup.h | 5 +++++
> include/linux/mm.h | 26 +++++++++++++-------------
> 2 files changed, 18 insertions(+), 13 deletions(-)
>
> diff --git a/include/asm-generic/5level-fixup.h b/include/asm-generic/5level-fixup.h
> index 58046ddc08d0..afbab31fbd7e 100644
> --- a/include/asm-generic/5level-fixup.h
> +++ b/include/asm-generic/5level-fixup.h
> @@ -17,6 +17,11 @@
> ((unlikely(pgd_none(*(p4d))) && __pud_alloc(mm, p4d, address)) ? \
> NULL : pud_offset(p4d, address))
>
> +#define pud_alloc_track(mm, p4d, address, mask) \
> + ((unlikely(pgd_none(*(p4d))) && \
> + (__pud_alloc(mm, p4d, address) || ({*(mask)|=PGTBL_P4D_MODIFIED;0;})))? \
> + NULL : pud_offset(p4d, address))
> +
> #define p4d_alloc(mm, pgd, address) (pgd)
> #define p4d_alloc_track(mm, pgd, address, mask) (pgd)
> #define p4d_offset(pgd, start) (pgd)
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 66e0977f970a..ad3b31c5bcc3 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -2088,35 +2088,35 @@ static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
> NULL : pud_offset(p4d, address);
> }
>
> -static inline p4d_t *p4d_alloc_track(struct mm_struct *mm, pgd_t *pgd,
> +static inline pud_t *pud_alloc_track(struct mm_struct *mm, p4d_t *p4d,
> unsigned long address,
> pgtbl_mod_mask *mod_mask)
> -
> {
> - if (unlikely(pgd_none(*pgd))) {
> - if (__p4d_alloc(mm, pgd, address))
> + if (unlikely(p4d_none(*p4d))) {
> + if (__pud_alloc(mm, p4d, address))
> return NULL;
> - *mod_mask |= PGTBL_PGD_MODIFIED;
> + *mod_mask |= PGTBL_P4D_MODIFIED;
> }
>
> - return p4d_offset(pgd, address);
> + return pud_offset(p4d, address);
> }
>
> -#endif /* !__ARCH_HAS_5LEVEL_HACK */
> -
> -static inline pud_t *pud_alloc_track(struct mm_struct *mm, p4d_t *p4d,
> +static inline p4d_t *p4d_alloc_track(struct mm_struct *mm, pgd_t *pgd,
> unsigned long address,
> pgtbl_mod_mask *mod_mask)
> +
> {
> - if (unlikely(p4d_none(*p4d))) {
> - if (__pud_alloc(mm, p4d, address))
> + if (unlikely(pgd_none(*pgd))) {
> + if (__p4d_alloc(mm, pgd, address))
> return NULL;
> - *mod_mask |= PGTBL_P4D_MODIFIED;
> + *mod_mask |= PGTBL_PGD_MODIFIED;
> }
>
> - return pud_offset(p4d, address);
> + return p4d_offset(pgd, address);
> }
>
> +#endif /* !__ARCH_HAS_5LEVEL_HACK */
> +
> static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
> {
> return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
> --
> 2.26.2
>
