xtensa: mm: fix PMD folding implementation

There was a definition of pmd_offset() in arch/xtensa/include/asm/pgtable.h
that shadowed the generic implementation defined in
include/asm-generic/pgtable-nopmd.h.

As the result, xtensa had shortcuts in page table traversal in several
places instead of doing level unfolding.

Remove local override for pmd_offset() and add page table unfolding where
necessary.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Message-Id: <1572964400-16542-2-git-send-email-rppt@kernel.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 3f7fe5a8c286d3647ecbf95e934e240538660f94..af72f02004f100fe7a433e8e1d7b1706a183698c 100644 (file)
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -371,9 +371,6 @@ ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 
 #define pgd_index(address)     ((address) >> PGDIR_SHIFT)
 
-/* Find an entry in the second-level page table.. */
-#define pmd_offset(dir,address) ((pmd_t*)(dir))
-
 /* Find an entry in the third-level page table.. */
 #define pte_index(address)     (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 #define pte_offset_kernel(dir,addr)                                    \

diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
index f81b1478da61bf1b62a2fe72fff3be01a18b6050..68a041402025667784f18f0cf71455745b7defef 100644 (file)
--- a/arch/xtensa/mm/fault.c
+++ b/arch/xtensa/mm/fault.c
@@ -197,6 +197,7 @@ vmalloc_fault:
                struct mm_struct *act_mm = current->active_mm;
                int index = pgd_index(address);
                pgd_t *pgd, *pgd_k;
+               pud_t *pud, *pud_k;
                pmd_t *pmd, *pmd_k;
                pte_t *pte_k;
 
@@ -211,8 +212,13 @@ vmalloc_fault:
 
                pgd_val(*pgd) = pgd_val(*pgd_k);
 
-               pmd = pmd_offset(pgd, address);
-               pmd_k = pmd_offset(pgd_k, address);
+               pud = pud_offset(pgd, address);
+               pud_k = pud_offset(pgd_k, address);
+               if (!pud_present(*pud) || !pud_present(*pud_k))
+                       goto bad_page_fault;
+
+               pmd = pmd_offset(pud, address);
+               pmd_k = pmd_offset(pud_k, address);
                if (!pmd_present(*pmd) || !pmd_present(*pmd_k))
                        goto bad_page_fault;
 

diff --git a/arch/xtensa/mm/kasan_init.c b/arch/xtensa/mm/kasan_init.c
index af7152560bc3ff3fd6a1d6bb0c194193057004f2..ace98bdf5191da4933c5b37d4c562901dd6c2403 100644 (file)
--- a/arch/xtensa/mm/kasan_init.c
+++ b/arch/xtensa/mm/kasan_init.c
@@ -20,7 +20,8 @@ void __init kasan_early_init(void)
 {
        unsigned long vaddr = KASAN_SHADOW_START;
        pgd_t *pgd = pgd_offset_k(vaddr);
-       pmd_t *pmd = pmd_offset(pgd, vaddr);
+       pud_t *pud = pud_offset(pgd, vaddr);
+       pmd_t *pmd = pmd_offset(pud, vaddr);
        int i;
 
        for (i = 0; i < PTRS_PER_PTE; ++i)
@@ -42,7 +43,8 @@ static void __init populate(void *start, void *end)
        unsigned long i, j;
        unsigned long vaddr = (unsigned long)start;
        pgd_t *pgd = pgd_offset_k(vaddr);
-       pmd_t *pmd = pmd_offset(pgd, vaddr);
+       pud_t *pud = pud_offset(pgd, vaddr);
+       pmd_t *pmd = pmd_offset(pud, vaddr);
        pte_t *pte = memblock_alloc(n_pages * sizeof(pte_t), PAGE_SIZE);
 
        if (!pte)

diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c
index 03678c4afc39b9e4ee94a3666b7ef630ad246d05..018dda2c6a9168db979c257b791948bbee4f2f28 100644 (file)
--- a/arch/xtensa/mm/mmu.c
+++ b/arch/xtensa/mm/mmu.c
@@ -22,7 +22,8 @@
 static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages)
 {
        pgd_t *pgd = pgd_offset_k(vaddr);
-       pmd_t *pmd = pmd_offset(pgd, vaddr);
+       pud_t *pud = pud_offset(pgd, vaddr);
+       pmd_t *pmd = pmd_offset(pud, vaddr);
        pte_t *pte;
        unsigned long i;
 

diff --git a/arch/xtensa/mm/tlb.c b/arch/xtensa/mm/tlb.c
index 59153d0aa8908dd415c975c87b9140650afa2686..164a2ca07a1f0e96b1324a64c0798fd5a49a3335 100644 (file)
--- a/arch/xtensa/mm/tlb.c
+++ b/arch/xtensa/mm/tlb.c
@@ -169,6 +169,7 @@ static unsigned get_pte_for_vaddr(unsigned vaddr)
        struct task_struct *task = get_current();
        struct mm_struct *mm = task->mm;
        pgd_t *pgd;
+       pud_t *pud;
        pmd_t *pmd;
        pte_t *pte;
 
@@ -177,7 +178,10 @@ static unsigned get_pte_for_vaddr(unsigned vaddr)
        pgd = pgd_offset(mm, vaddr);
        if (pgd_none_or_clear_bad(pgd))
                return 0;
-       pmd = pmd_offset(pgd, vaddr);
+       pud = pud_offset(pgd, vaddr);
+       if (pud_none_or_clear_bad(pud))
+               return 0;
+       pmd = pmd_offset(pud, vaddr);
        if (pmd_none_or_clear_bad(pmd))
                return 0;
        pte = pte_offset_map(pmd, vaddr);