[PATCH v3 2/2] powerpc/mm/radix: Free PUD table when freeing pagetable

[Bharata B Rao <bharata@linux.ibm.com>]

remove_pagetable() isn't freeing PUD table. This causes memory
leak during memory unplug. Fix this.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
---
 arch/powerpc/mm/book3s64/radix_pgtable.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index c440446ee00f..860eb37736c0 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -783,6 +783,21 @@ static void free_pmd_table(pmd_t *pmd_start, pud_t *pud)
 	pud_clear(pud);
 }
 
+static void free_pud_table(pud_t *pud_start, pgd_t *pgd)
+{
+	pud_t *pud;
+	int i;
+
+	for (i = 0; i < PTRS_PER_PUD; i++) {
+		pud = pud_start + i;
+		if (!pud_none(*pud))
+			return;
+	}
+
+	pud_free(&init_mm, pud_start);
+	pgd_clear(pgd);
+}
+
 struct change_mapping_params {
 	pte_t *pte;
 	unsigned long start;
@@ -953,6 +968,7 @@ static void __meminit remove_pagetable(unsigned long start, unsigned long end)
 
 		pud_base = (pud_t *)pgd_page_vaddr(*pgd);
 		remove_pud_table(pud_base, addr, next);
+		free_pud_table(pud_base, pgd);
 	}
 
 	spin_unlock(&init_mm.page_table_lock);
-- 
2.21.0