| Message ID | 20200902114222.181353-10-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm/debug_vm_pgtable fixes | expand |
On 09/02/2020 05:12 PM, Aneesh Kumar K.V wrote: > Make sure we call pte accessors with correct lock held. > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> > --- > mm/debug_vm_pgtable.c | 35 ++++++++++++++++++++++------------- > 1 file changed, 22 insertions(+), 13 deletions(-) > > diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c > index f59cf6a9b05e..2bc1952e5f83 100644 > --- a/mm/debug_vm_pgtable.c > +++ b/mm/debug_vm_pgtable.c > @@ -1035,30 +1035,39 @@ static int __init debug_vm_pgtable(void) > > hugetlb_basic_tests(pte_aligned, prot); > > - pte_clear_tests(mm, ptep, vaddr); > - pmd_clear_tests(mm, pmdp); > - pud_clear_tests(mm, pudp); > - p4d_clear_tests(mm, p4dp); > - pgd_clear_tests(mm, pgdp); > + /* > + * Page table modifying tests. They need to hold > + * proper page table lock. > + */ > > ptl = pte_lockptr(mm, pmdp); > spin_lock(ptl); > - > + pte_clear_tests(mm, ptep, vaddr); > pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); > - pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot); > - pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot); > - hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); > - > + pte_unmap_unlock(ptep, ptl); > > + ptl = pmd_lock(mm, pmdp); > + pmd_clear_tests(mm, pmdp); > + pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot); > pmd_huge_tests(pmdp, pmd_aligned, prot); > + pmd_populate_tests(mm, pmdp, saved_ptep); > + spin_unlock(ptl); > + > + ptl = pud_lock(mm, pudp); > + pud_clear_tests(mm, pudp); > + pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot); > pud_huge_tests(pudp, pud_aligned, prot); > + pud_populate_tests(mm, pudp, saved_pmdp); > + spin_unlock(ptl); > > - pte_unmap_unlock(ptep, ptl); > + hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); > > - pmd_populate_tests(mm, pmdp, saved_ptep); > - pud_populate_tests(mm, pudp, saved_pmdp); > + spin_lock(&mm->page_table_lock); > + p4d_clear_tests(mm, p4dp); > + pgd_clear_tests(mm, pgdp); > p4d_populate_tests(mm, p4dp, saved_pudp); > pgd_populate_tests(mm, pgdp, saved_p4dp); > + spin_unlock(&mm->page_table_lock); > > p4d_free(mm, saved_p4dp); > pud_free(mm, saved_pudp); > This patch, in itself looks good but will probably require folding with the previous one to prevent the git bisect problem on arm64.
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index f59cf6a9b05e..2bc1952e5f83 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -1035,30 +1035,39 @@ static int __init debug_vm_pgtable(void) hugetlb_basic_tests(pte_aligned, prot); - pte_clear_tests(mm, ptep, vaddr); - pmd_clear_tests(mm, pmdp); - pud_clear_tests(mm, pudp); - p4d_clear_tests(mm, p4dp); - pgd_clear_tests(mm, pgdp); + /* + * Page table modifying tests. They need to hold + * proper page table lock. + */ ptl = pte_lockptr(mm, pmdp); spin_lock(ptl); - + pte_clear_tests(mm, ptep, vaddr); pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); - pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot); - pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot); - hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); - + pte_unmap_unlock(ptep, ptl); + ptl = pmd_lock(mm, pmdp); + pmd_clear_tests(mm, pmdp); + pmd_advanced_tests(mm, vma, pmdp, pmd_aligned, vaddr, prot); pmd_huge_tests(pmdp, pmd_aligned, prot); + pmd_populate_tests(mm, pmdp, saved_ptep); + spin_unlock(ptl); + + ptl = pud_lock(mm, pudp); + pud_clear_tests(mm, pudp); + pud_advanced_tests(mm, vma, pudp, pud_aligned, vaddr, prot); pud_huge_tests(pudp, pud_aligned, prot); + pud_populate_tests(mm, pudp, saved_pmdp); + spin_unlock(ptl); - pte_unmap_unlock(ptep, ptl); + hugetlb_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot); - pmd_populate_tests(mm, pmdp, saved_ptep); - pud_populate_tests(mm, pudp, saved_pmdp); + spin_lock(&mm->page_table_lock); + p4d_clear_tests(mm, p4dp); + pgd_clear_tests(mm, pgdp); p4d_populate_tests(mm, p4dp, saved_pudp); pgd_populate_tests(mm, pgdp, saved_p4dp); + spin_unlock(&mm->page_table_lock); p4d_free(mm, saved_p4dp); pud_free(mm, saved_pudp);
Make sure we call pte accessors with correct lock held. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- mm/debug_vm_pgtable.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-)