On Sun, Feb 11, 2018 at 08:30:06PM +0530, Aneesh Kumar K.V wrote:
> To support memory keys, we moved the hash pte slot information to the second
> half of the page table. This was ok with PTE entries at level 4 and level 3.
> We already allocate larger page table pages at those level to accomodate extra
> details. For level 4 we already have the extra space which was used to track
> 4k hash page table entry details and at pmd level the extra space was
> allocated
> to track the THP details.
>
> With hugetlbfs PTE, we used this extra space at the PMD level to store the
> slot details. But we also support hugetlbfs PTE at PUD leve and PUD level page
> didn't allocate extra space. This resulted in memory corruption.
>
> Fix this by allocating extra space at PUD level when HUGETLB is enabled. We
> may need further changes to allocate larger space at PMD level when we enable
> HUGETLB. That will be done in next patch.
>
> Fixes:bf9a95f9a6481bc6e(" powerpc: Free up four 64K PTE bits in 64K backed
> HPTE pages")
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
> ---
> arch/powerpc/include/asm/book3s/32/pgtable.h | 1 +
> arch/powerpc/include/asm/book3s/64/hash-64k.h | 5 +++++
> arch/powerpc/include/asm/book3s/64/hash.h | 10 ++++++++++
> arch/powerpc/include/asm/book3s/64/pgalloc.h | 6 +++---
> arch/powerpc/include/asm/book3s/64/pgtable.h | 2 ++
> arch/powerpc/include/asm/nohash/32/pgtable.h | 1 +
> arch/powerpc/include/asm/nohash/64/pgtable.h | 1 +
> arch/powerpc/mm/hash_utils_64.c | 1 +
> arch/powerpc/mm/init-common.c | 4 ++--
> arch/powerpc/mm/pgtable-radix.c | 1 +
> arch/powerpc/mm/pgtable_64.c | 2 ++
> 11 files changed, 29 insertions(+), 5 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h
> b/arch/powerpc/include/asm/book3s/32/pgtable.h
> index 30a155c0a6b0..c615abdce119 100644
> --- a/arch/powerpc/include/asm/book3s/32/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
> @@ -16,6 +16,7 @@
> #define PGD_INDEX_SIZE (32 - PGDIR_SHIFT)
>
> #define PMD_CACHE_INDEX PMD_INDEX_SIZE
> +#define PUD_CACHE_INDEX PUD_INDEX_SIZE
>
> #ifndef __ASSEMBLY__
> #define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
> diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> index 338b7da468ce..c08b3b032ec0 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
> @@ -146,7 +146,12 @@ static inline int hash__remap_4k_pfn(struct
> vm_area_struct *vma, unsigned long a
> #else
> #define H_PMD_TABLE_SIZE (sizeof(pmd_t) << PMD_INDEX_SIZE)
> #endif
> +#ifdef CONFIG_HUGETLB_PAGE
> +#define H_PUD_TABLE_SIZE ((sizeof(pud_t) << PUD_INDEX_SIZE) + \
> + (sizeof(unsigned long) << PUD_INDEX_SIZE))
> +#else
> #define H_PUD_TABLE_SIZE (sizeof(pud_t) << PUD_INDEX_SIZE)
> +#endif
> #define H_PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
>
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> diff --git a/arch/powerpc/include/asm/book3s/64/hash.h
> b/arch/powerpc/include/asm/book3s/64/hash.h
> index 0920eff731b3..234f141fb151 100644
> --- a/arch/powerpc/include/asm/book3s/64/hash.h
> +++ b/arch/powerpc/include/asm/book3s/64/hash.h
> @@ -32,6 +32,16 @@
> #else
> #define H_PMD_CACHE_INDEX H_PMD_INDEX_SIZE
> #endif
> +/*
> + * We not store the slot details in the second half of page table.
s/not//
We store....
Reviewed-by: Ram Pai <linux...@us.ibm.com>
