diff options
Diffstat (limited to 'arch/x86/mm/init_32.c')
| -rw-r--r-- | arch/x86/mm/init_32.c | 68 |
1 files changed, 25 insertions, 43 deletions
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 030bfed10a6c..f34d275ee201 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -56,8 +56,6 @@ unsigned long highstart_pfn, highend_pfn; -static noinline int do_test_wp_bit(void); - bool __read_mostly __vmalloc_start_set = false; /* @@ -67,6 +65,7 @@ bool __read_mostly __vmalloc_start_set = false; */ static pmd_t * __init one_md_table_init(pgd_t *pgd) { + p4d_t *p4d; pud_t *pud; pmd_t *pmd_table; @@ -75,13 +74,15 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd) pmd_table = (pmd_t *)alloc_low_page(); paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT); set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT)); - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + pud = pud_offset(p4d, 0); BUG_ON(pmd_table != pmd_offset(pud, 0)); return pmd_table; } #endif - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + pud = pud_offset(p4d, 0); pmd_table = pmd_offset(pud, 0); return pmd_table; @@ -390,8 +391,11 @@ pte_t *kmap_pte; static inline pte_t *kmap_get_fixmap_pte(unsigned long vaddr) { - return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), - vaddr), vaddr), vaddr); + pgd_t *pgd = pgd_offset_k(vaddr); + p4d_t *p4d = p4d_offset(pgd, vaddr); + pud_t *pud = pud_offset(p4d, vaddr); + pmd_t *pmd = pmd_offset(pud, vaddr); + return pte_offset_kernel(pmd, vaddr); } static void __init kmap_init(void) @@ -410,6 +414,7 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base) { unsigned long vaddr; pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pte_t *pte; @@ -418,7 +423,8 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base) page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base); pgd = swapper_pg_dir + pgd_index(vaddr); - pud = pud_offset(pgd, vaddr); + p4d = p4d_offset(pgd, vaddr); + pud = pud_offset(p4d, vaddr); pmd = pmd_offset(pud, vaddr); pte = pte_offset_kernel(pmd, vaddr); pkmap_page_table = pte; @@ -450,6 +456,7 @@ void __init native_pagetable_init(void) { unsigned long pfn, va; pgd_t *pgd, *base = swapper_pg_dir; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pte_t *pte; @@ -469,7 +476,8 @@ void __init native_pagetable_init(void) if (!pgd_present(*pgd)) break; - pud = pud_offset(pgd, va); + p4d = p4d_offset(pgd, va); + pud = pud_offset(p4d, va); pmd = pmd_offset(pud, va); if (!pmd_present(*pmd)) break; @@ -716,22 +724,20 @@ void __init paging_init(void) */ static void __init test_wp_bit(void) { - int wp_works_ok; + char z = 0; - printk(KERN_INFO - "Checking if this processor honours the WP bit even in supervisor mode..."); + printk(KERN_INFO "Checking if this processor honours the WP bit even in supervisor mode..."); - /* Any page-aligned address will do, the test is non-destructive */ - __set_fixmap(FIX_WP_TEST, __pa(&swapper_pg_dir), PAGE_KERNEL_RO); - wp_works_ok = do_test_wp_bit(); - clear_fixmap(FIX_WP_TEST); + __set_fixmap(FIX_WP_TEST, __pa_symbol(empty_zero_page), PAGE_KERNEL_RO); - if (!wp_works_ok) { - printk(KERN_CONT "No.\n"); - panic("Linux doesn't support CPUs with broken WP."); - } else { + if (probe_kernel_write((char *)fix_to_virt(FIX_WP_TEST), &z, 1)) { + clear_fixmap(FIX_WP_TEST); printk(KERN_CONT "Ok.\n"); + return; } + + printk(KERN_CONT "No.\n"); + panic("Linux doesn't support CPUs with broken WP."); } void __init mem_init(void) @@ -841,30 +847,6 @@ int arch_remove_memory(u64 start, u64 size) #endif #endif -/* - * This function cannot be __init, since exceptions don't work in that - * section. Put this after the callers, so that it cannot be inlined. - */ -static noinline int do_test_wp_bit(void) -{ - char tmp_reg; - int flag; - - __asm__ __volatile__( - " movb %0, %1 \n" - "1: movb %1, %0 \n" - " xorl %2, %2 \n" - "2: \n" - _ASM_EXTABLE(1b,2b) - :"=m" (*(char *)fix_to_virt(FIX_WP_TEST)), - "=q" (tmp_reg), - "=r" (flag) - :"2" (1) - :"memory"); - - return flag; -} - int kernel_set_to_readonly __read_mostly; void set_kernel_text_rw(void) |