| Message ID | 20210202091116.196134-3-aneesh.kumar@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [RFC,1/6] selftest/mremap_test: Update the test to handle pagesize other than 4K | expand |
On Tue, Feb 02, 2021 at 02:41:13PM +0530, Aneesh Kumar K.V wrote: > pmd/pud_populate is the right interface to be used to set the respective > page table entries. Some architectures do assume that set_pmd/pud_at > can only be used to set a hugepage PTE. Since we are not setting up a hugepage > PTE here, use the pmd/pud_populate interface. Since you did the audit, it might be nice to record which architectures that are. Also, how much work to fix them?
On 2/2/21 4:17 PM, Peter Zijlstra wrote: > On Tue, Feb 02, 2021 at 02:41:13PM +0530, Aneesh Kumar K.V wrote: >> pmd/pud_populate is the right interface to be used to set the respective >> page table entries. Some architectures do assume that set_pmd/pud_at >> can only be used to set a hugepage PTE. Since we are not setting up a hugepage >> PTE here, use the pmd/pud_populate interface. > > Since you did the audit, it might be nice to record which architectures > that are. Also, how much work to fix them? > I didn't audit them completely primarily because I don't follow the page table format of other archs. But I guess arm64, s390 appears to make that assumption. Moreover set_pmd_at was added as part of THP patch series. BTW why should we fix those architectures ? isn't pmd_populate the right interface for updating pmd entries other than hugepage pte ? -aneesh
diff --git a/mm/mremap.c b/mm/mremap.c index f554320281cc..54fd2302b99d 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -27,6 +27,7 @@ #include <asm/cacheflush.h> #include <asm/tlbflush.h> +#include <asm/pgalloc.h> #include "internal.h" @@ -258,9 +259,8 @@ static bool move_normal_pmd(struct vm_area_struct *vma, unsigned long old_addr, pmd_clear(old_pmd); VM_BUG_ON(!pmd_none(*new_pmd)); + pmd_populate(mm, new_pmd, (pgtable_t)pmd_page_vaddr(pmd)); - /* Set the new pmd */ - set_pmd_at(mm, new_addr, new_pmd, pmd); flush_tlb_range(vma, old_addr, old_addr + PMD_SIZE); if (new_ptl != old_ptl) spin_unlock(new_ptl); @@ -307,8 +307,7 @@ static bool move_normal_pud(struct vm_area_struct *vma, unsigned long old_addr, VM_BUG_ON(!pud_none(*new_pud)); - /* Set the new pud */ - set_pud_at(mm, new_addr, new_pud, pud); + pud_populate(mm, new_pud, (pmd_t *)pud_page_vaddr(pud)); flush_tlb_range(vma, old_addr, old_addr + PUD_SIZE); if (new_ptl != old_ptl) spin_unlock(new_ptl);
pmd/pud_populate is the right interface to be used to set the respective page table entries. Some architectures do assume that set_pmd/pud_at can only be used to set a hugepage PTE. Since we are not setting up a hugepage PTE here, use the pmd/pud_populate interface. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> --- mm/mremap.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)