| Message ID | 20181128143438.29458-5-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | NestMMU pte upgrade workaround for mprotect | expand |
On Wed, 28 Nov 2018 20:04:37 +0530 "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> wrote: > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Some explanation of the motivation would be useful. > include/linux/hugetlb.h | 18 ++++++++++++++++++ > mm/hugetlb.c | 8 +++++--- > 2 files changed, 23 insertions(+), 3 deletions(-) > > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > index 087fd5f48c91..e2a3b0c854eb 100644 > --- a/include/linux/hugetlb.h > +++ b/include/linux/hugetlb.h > @@ -543,6 +543,24 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr > set_huge_pte_at(mm, addr, ptep, pte); > } > #endif > + > +#ifndef huge_ptep_modify_prot_start > +static inline pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep) > +{ > + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep); > +} > +#endif #define huge_ptep_modify_prot_start huge_ptep_modify_prot_start > +#ifndef huge_ptep_modify_prot_commit > +static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma, > + unsigned long addr, pte_t *ptep, > + pte_t old_pte, pte_t pte) > +{ > + set_huge_pte_at(vma->vm_mm, addr, ptep, pte); > +} > +#endif #define huge_ptep_modify_prot_commit huge_ptep_modify_prot_commit
On 11/29/18 3:40 AM, Andrew Morton wrote: > On Wed, 28 Nov 2018 20:04:37 +0530 "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> wrote: > >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> > > Some explanation of the motivation would be useful. I will update the commit message. > >> include/linux/hugetlb.h | 18 ++++++++++++++++++ >> mm/hugetlb.c | 8 +++++--- >> 2 files changed, 23 insertions(+), 3 deletions(-) >> >> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h >> index 087fd5f48c91..e2a3b0c854eb 100644 >> --- a/include/linux/hugetlb.h >> +++ b/include/linux/hugetlb.h >> @@ -543,6 +543,24 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr >> set_huge_pte_at(mm, addr, ptep, pte); >> } >> #endif >> + >> +#ifndef huge_ptep_modify_prot_start >> +static inline pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, >> + unsigned long addr, pte_t *ptep) >> +{ >> + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep); >> +} >> +#endif > > #define huge_ptep_modify_prot_start huge_ptep_modify_prot_start > >> +#ifndef huge_ptep_modify_prot_commit >> +static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma, >> + unsigned long addr, pte_t *ptep, >> + pte_t old_pte, pte_t pte) >> +{ >> + set_huge_pte_at(vma->vm_mm, addr, ptep, pte); >> +} >> +#endif > > #define huge_ptep_modify_prot_commit huge_ptep_modify_prot_commit > > Will update. -aneesh
"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> writes: > On 11/29/18 3:40 AM, Andrew Morton wrote: >> On Wed, 28 Nov 2018 20:04:37 +0530 "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> wrote: >> >>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> >> >> Some explanation of the motivation would be useful. > > I will update the commit message. > Is this good? mm/hugetlb: Add prot_modify_start/commit sequence for hugetlb update Architectures like ppc64 requires to do a conditional tlb flush based on the old and new value of pte. Follow the regular pte change protection sequence for hugetlb too. This allow the architectures to override the update sequence. -aneesh
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 087fd5f48c91..e2a3b0c854eb 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -543,6 +543,24 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr set_huge_pte_at(mm, addr, ptep, pte); } #endif + +#ifndef huge_ptep_modify_prot_start +static inline pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep) +{ + return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep); +} +#endif + +#ifndef huge_ptep_modify_prot_commit +static inline void huge_ptep_modify_prot_commit(struct vm_area_struct *vma, + unsigned long addr, pte_t *ptep, + pte_t old_pte, pte_t pte) +{ + set_huge_pte_at(vma->vm_mm, addr, ptep, pte); +} +#endif + #else /* CONFIG_HUGETLB_PAGE */ struct hstate {}; #define alloc_huge_page(v, a, r) NULL diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7f2a28ab46d5..e5f5cda14f28 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4388,10 +4388,12 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, continue; } if (!huge_pte_none(pte)) { - pte = huge_ptep_get_and_clear(mm, address, ptep); - pte = pte_mkhuge(huge_pte_modify(pte, newprot)); + pte_t old_pte; + + old_pte = huge_ptep_modify_prot_start(vma, address, ptep); + pte = pte_mkhuge(huge_pte_modify(old_pte, newprot)); pte = arch_make_huge_pte(pte, vma, NULL, 0); - set_huge_pte_at(mm, address, ptep, pte); + huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); pages++; } spin_unlock(ptl);
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- include/linux/hugetlb.h | 18 ++++++++++++++++++ mm/hugetlb.c | 8 +++++--- 2 files changed, 23 insertions(+), 3 deletions(-)