| Message ID | 20200812063358.369514-9-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/16] powerpc/mm: Add DEBUG_VM WARN for pmd_clear | expand |
On 08/12/2020 12:03 PM, Aneesh Kumar K.V wrote: > set_pud_at() should not be used to set a pte entry at locations that > already holds a valid pte entry. Architectures like ppc64 don't do TLB > invalidate in set_pud_at() and hence expect it to be used to set locations > that are not a valid PTE. > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> > --- > mm/debug_vm_pgtable.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index 60bf876081b8..644d28861ce9 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -278,9 +278,6 @@ static void __init pud_advanced_tests(struct mm_struct *mm, > WARN_ON(pud_write(pud)); > > #ifndef __PAGETABLE_PMD_FOLDED > - > - pud = pud_mkhuge(pfn_pud(pfn, prot)); > - set_pud_at(mm, vaddr, pudp, pud); > pudp_huge_get_and_clear(mm, vaddr, pudp); > pud = READ_ONCE(*pudp); > WARN_ON(!pud_none(pud)); > @@ -302,6 +299,11 @@ static void __init pud_advanced_tests(struct mm_struct *mm, > pud = READ_ONCE(*pudp); > WARN_ON(!(pud_write(pud) && pud_dirty(pud))); > > + pudp_huge_get_and_clear_full(vma, vaddr, pudp, 1); > + pud = READ_ONCE(*pudp); > + WARN_ON(!pud_none(pud)); > + > + pud = pud_mkhuge(pfn_pud(pfn, prot)); > pud = pud_mkyoung(pud); > set_pud_at(mm, vaddr, pudp, pud); > pudp_test_and_clear_young(vma, vaddr, pudp); Very similar to [PATCH 3/16] wrt set_pte_at(), please fold it.
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 60bf876081b8..644d28861ce9 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -278,9 +278,6 @@ static void __init pud_advanced_tests(struct mm_struct *mm, WARN_ON(pud_write(pud)); #ifndef __PAGETABLE_PMD_FOLDED - - pud = pud_mkhuge(pfn_pud(pfn, prot)); - set_pud_at(mm, vaddr, pudp, pud); pudp_huge_get_and_clear(mm, vaddr, pudp); pud = READ_ONCE(*pudp); WARN_ON(!pud_none(pud)); @@ -302,6 +299,11 @@ static void __init pud_advanced_tests(struct mm_struct *mm, pud = READ_ONCE(*pudp); WARN_ON(!(pud_write(pud) && pud_dirty(pud))); + pudp_huge_get_and_clear_full(vma, vaddr, pudp, 1); + pud = READ_ONCE(*pudp); + WARN_ON(!pud_none(pud)); + + pud = pud_mkhuge(pfn_pud(pfn, prot)); pud = pud_mkyoung(pud); set_pud_at(mm, vaddr, pudp, pud); pudp_test_and_clear_young(vma, vaddr, pudp);
set_pud_at() should not be used to set a pte entry at locations that already holds a valid pte entry. Architectures like ppc64 don't do TLB invalidate in set_pud_at() and hence expect it to be used to set locations that are not a valid PTE. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- mm/debug_vm_pgtable.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)