Commit f0d1eab8 authored by Mike Rapoport's avatar Mike Rapoport Committed by Max Filippov
Browse files

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: default avatarMike Rapoport <rppt@linux.ibm.com>
Message-Id: <1572964400-16542-2-git-send-email-rppt@kernel.org>
Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent 8951eb15

arch/xtensa/include/asm/pgtable.h

+0 −3
Original line number Diff line number Diff line
@@ -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) 					\

arch/xtensa/mm/fault.c

+8 −2
Original line number Diff line number Diff line
@@ -197,6 +197,7 @@ void do_page_fault(struct pt_regs *regs) 
		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 @@ void do_page_fault(struct pt_regs *regs) 


		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;

arch/xtensa/mm/kasan_init.c

+4 −2
Original line number Diff line number Diff line
@@ -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)

arch/xtensa/mm/mmu.c

+2 −1
Original line number Diff line number Diff line
@@ -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;

arch/xtensa/mm/tlb.c

+5 −1
Original line number Diff line number Diff line
@@ -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);