From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> Subject: powerpc/mm: move setting pte specific flags to pfn_pte powerpc used to set the pte specific flags in set_pte_at(). This is different from other architectures. To be consistent with other architecture update pfn_pte to set _PAGE_PTE on ppc64. Also, drop now unused pte_mkpte. We add a VM_WARN_ON() to catch the usage of calling set_pte_at() without setting _PAGE_PTE bit. We will remove that after a few releases. With respect to huge pmd entries, pmd_mkhuge() takes care of adding the _PAGE_PTE bit. [akpm@xxxxxxxxxxxxxxxxxxxx: whitespace fix, per Christophe] Link: https://lkml.kernel.org/r/20200902114222.181353-3-aneesh.kumar@xxxxxxxxxxxxx Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/book3s/64/pgtable.h | 15 +++++++++------ arch/powerpc/include/asm/nohash/pgtable.h | 5 ----- arch/powerpc/mm/pgtable.c | 5 ----- 3 files changed, 9 insertions(+), 16 deletions(-) --- a/arch/powerpc/include/asm/book3s/64/pgtable.h~powerpc-mm-move-setting-pte-specific-flags-to-pfn_pte +++ a/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -615,7 +615,7 @@ static inline pte_t pfn_pte(unsigned lon VM_BUG_ON(pfn >> (64 - PAGE_SHIFT)); VM_BUG_ON((pfn << PAGE_SHIFT) & ~PTE_RPN_MASK); - return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot)); + return __pte(((pte_basic_t)pfn << PAGE_SHIFT) | pgprot_val(pgprot) | _PAGE_PTE); } static inline unsigned long pte_pfn(pte_t pte) @@ -651,11 +651,6 @@ static inline pte_t pte_mkexec(pte_t pte return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_EXEC)); } -static inline pte_t pte_mkpte(pte_t pte) -{ - return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE)); -} - static inline pte_t pte_mkwrite(pte_t pte) { /* @@ -819,6 +814,14 @@ static inline int pte_none(pte_t pte) static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte, int percpu) { + + VM_WARN_ON(!(pte_raw(pte) & cpu_to_be64(_PAGE_PTE))); + /* + * Keep the _PAGE_PTE added till we are sure we handle _PAGE_PTE + * in all the callers. + */ + pte = __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PTE)); + if (radix_enabled()) return radix__set_pte_at(mm, addr, ptep, pte, percpu); return hash__set_pte_at(mm, addr, ptep, pte, percpu); --- a/arch/powerpc/include/asm/nohash/pgtable.h~powerpc-mm-move-setting-pte-specific-flags-to-pfn_pte +++ a/arch/powerpc/include/asm/nohash/pgtable.h @@ -140,11 +140,6 @@ static inline pte_t pte_mkold(pte_t pte) return __pte(pte_val(pte) & ~_PAGE_ACCESSED); } -static inline pte_t pte_mkpte(pte_t pte) -{ - return pte; -} - static inline pte_t pte_mkspecial(pte_t pte) { return __pte(pte_val(pte) | _PAGE_SPECIAL); --- a/arch/powerpc/mm/pgtable.c~powerpc-mm-move-setting-pte-specific-flags-to-pfn_pte +++ a/arch/powerpc/mm/pgtable.c @@ -184,9 +184,6 @@ void set_pte_at(struct mm_struct *mm, un */ VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep)); - /* Add the pte bit when trying to set a pte */ - pte = pte_mkpte(pte); - /* Note: mm->context.id might not yet have been assigned as * this context might not have been activated yet when this * is called. @@ -275,8 +272,6 @@ void set_huge_pte_at(struct mm_struct *m */ VM_WARN_ON(pte_hw_valid(*ptep) && !pte_protnone(*ptep)); - pte = pte_mkpte(pte); - pte = set_pte_filter(pte); val = pte_val(pte); _
