diff options
Diffstat (limited to 'arch/i386/mm')
-rw-r--r-- | arch/i386/mm/discontig.c | 12 | ||||
-rw-r--r-- | arch/i386/mm/fault.c | 210 | ||||
-rw-r--r-- | arch/i386/mm/hugetlbpage.c | 12 | ||||
-rw-r--r-- | arch/i386/mm/init.c | 47 | ||||
-rw-r--r-- | arch/i386/mm/pageattr.c | 20 | ||||
-rw-r--r-- | arch/i386/mm/pgtable.c | 2 |
6 files changed, 176 insertions, 127 deletions
diff --git a/arch/i386/mm/discontig.c b/arch/i386/mm/discontig.c index c4af9638dbfa..fe6eb901326e 100644 --- a/arch/i386/mm/discontig.c +++ b/arch/i386/mm/discontig.c @@ -31,6 +31,7 @@ #include <linux/nodemask.h> #include <linux/module.h> #include <linux/kexec.h> +#include <linux/pfn.h> #include <asm/e820.h> #include <asm/setup.h> @@ -352,17 +353,6 @@ void __init zone_sizes_init(void) { int nid; - /* - * Insert nodes into pgdat_list backward so they appear in order. - * Clobber node 0's links and NULL out pgdat_list before starting. - */ - pgdat_list = NULL; - for (nid = MAX_NUMNODES - 1; nid >= 0; nid--) { - if (!node_online(nid)) - continue; - NODE_DATA(nid)->pgdat_next = pgdat_list; - pgdat_list = NODE_DATA(nid); - } for_each_online_node(nid) { unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0}; diff --git a/arch/i386/mm/fault.c b/arch/i386/mm/fault.c index cf572d9a3b6e..7f0fcf219a26 100644 --- a/arch/i386/mm/fault.c +++ b/arch/i386/mm/fault.c @@ -214,6 +214,68 @@ static noinline void force_sig_info_fault(int si_signo, int si_code, fastcall void do_invalid_op(struct pt_regs *, unsigned long); +static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) +{ + unsigned index = pgd_index(address); + pgd_t *pgd_k; + pud_t *pud, *pud_k; + pmd_t *pmd, *pmd_k; + + pgd += index; + pgd_k = init_mm.pgd + index; + + if (!pgd_present(*pgd_k)) + return NULL; + + /* + * set_pgd(pgd, *pgd_k); here would be useless on PAE + * and redundant with the set_pmd() on non-PAE. As would + * set_pud. + */ + + pud = pud_offset(pgd, address); + pud_k = pud_offset(pgd_k, address); + if (!pud_present(*pud_k)) + return NULL; + + pmd = pmd_offset(pud, address); + pmd_k = pmd_offset(pud_k, address); + if (!pmd_present(*pmd_k)) + return NULL; + if (!pmd_present(*pmd)) + set_pmd(pmd, *pmd_k); + else + BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k)); + return pmd_k; +} + +/* + * Handle a fault on the vmalloc or module mapping area + * + * This assumes no large pages in there. + */ +static inline int vmalloc_fault(unsigned long address) +{ + unsigned long pgd_paddr; + pmd_t *pmd_k; + pte_t *pte_k; + /* + * Synchronize this task's top level page-table + * with the 'reference' page table. + * + * Do _not_ use "current" here. We might be inside + * an interrupt in the middle of a task switch.. + */ + pgd_paddr = read_cr3(); + pmd_k = vmalloc_sync_one(__va(pgd_paddr), address); + if (!pmd_k) + return -1; + pte_k = pte_offset_kernel(pmd_k, address); + if (!pte_present(*pte_k)) + return -1; + return 0; +} + /* * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate @@ -223,6 +285,8 @@ fastcall void do_invalid_op(struct pt_regs *, unsigned long); * bit 0 == 0 means no page found, 1 means protection fault * bit 1 == 0 means read, 1 means write * bit 2 == 0 means kernel, 1 means user-mode + * bit 3 == 1 means use of reserved bit detected + * bit 4 == 1 means fault was an instruction fetch */ fastcall void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) @@ -237,13 +301,6 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs, /* get the address */ address = read_cr2(); - if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, - SIGSEGV) == NOTIFY_STOP) - return; - /* It's safe to allow irq's after cr2 has been saved */ - if (regs->eflags & (X86_EFLAGS_IF|VM_MASK)) - local_irq_enable(); - tsk = current; si_code = SEGV_MAPERR; @@ -259,17 +316,29 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs, * * This verifies that the fault happens in kernel space * (error_code & 4) == 0, and that the fault was not a - * protection error (error_code & 1) == 0. + * protection error (error_code & 9) == 0. */ - if (unlikely(address >= TASK_SIZE)) { - if (!(error_code & 5)) - goto vmalloc_fault; - /* + if (unlikely(address >= TASK_SIZE)) { + if (!(error_code & 0x0000000d) && vmalloc_fault(address) >= 0) + return; + if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, + SIGSEGV) == NOTIFY_STOP) + return; + /* * Don't take the mm semaphore here. If we fixup a prefetch * fault we could otherwise deadlock. */ goto bad_area_nosemaphore; - } + } + + if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14, + SIGSEGV) == NOTIFY_STOP) + return; + + /* It's safe to allow irq's after cr2 has been saved and the vmalloc + fault has been handled. */ + if (regs->eflags & (X86_EFLAGS_IF|VM_MASK)) + local_irq_enable(); mm = tsk->mm; @@ -440,24 +509,31 @@ no_context: bust_spinlocks(1); -#ifdef CONFIG_X86_PAE - if (error_code & 16) { - pte_t *pte = lookup_address(address); + if (oops_may_print()) { + #ifdef CONFIG_X86_PAE + if (error_code & 16) { + pte_t *pte = lookup_address(address); - if (pte && pte_present(*pte) && !pte_exec_kernel(*pte)) - printk(KERN_CRIT "kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n", current->uid); + if (pte && pte_present(*pte) && !pte_exec_kernel(*pte)) + printk(KERN_CRIT "kernel tried to execute " + "NX-protected page - exploit attempt? " + "(uid: %d)\n", current->uid); + } + #endif + if (address < PAGE_SIZE) + printk(KERN_ALERT "BUG: unable to handle kernel NULL " + "pointer dereference"); + else + printk(KERN_ALERT "BUG: unable to handle kernel paging" + " request"); + printk(" at virtual address %08lx\n",address); + printk(KERN_ALERT " printing eip:\n"); + printk("%08lx\n", regs->eip); } -#endif - if (address < PAGE_SIZE) - printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference"); - else - printk(KERN_ALERT "Unable to handle kernel paging request"); - printk(" at virtual address %08lx\n",address); - printk(KERN_ALERT " printing eip:\n"); - printk("%08lx\n", regs->eip); page = read_cr3(); page = ((unsigned long *) __va(page))[address >> 22]; - printk(KERN_ALERT "*pde = %08lx\n", page); + if (oops_may_print()) + printk(KERN_ALERT "*pde = %08lx\n", page); /* * We must not directly access the pte in the highpte * case, the page table might be allocated in highmem. @@ -465,7 +541,7 @@ no_context: * it's allocated already. */ #ifndef CONFIG_HIGHPTE - if (page & 1) { + if ((page & 1) && oops_may_print()) { page &= PAGE_MASK; address &= 0x003ff000; page = ((unsigned long *) __va(page))[address >> PAGE_SHIFT]; @@ -510,51 +586,41 @@ do_sigbus: tsk->thread.error_code = error_code; tsk->thread.trap_no = 14; force_sig_info_fault(SIGBUS, BUS_ADRERR, address, tsk); - return; - -vmalloc_fault: - { - /* - * Synchronize this task's top level page-table - * with the 'reference' page table. - * - * Do _not_ use "tsk" here. We might be inside - * an interrupt in the middle of a task switch.. - */ - int index = pgd_index(address); - unsigned long pgd_paddr; - pgd_t *pgd, *pgd_k; - pud_t *pud, *pud_k; - pmd_t *pmd, *pmd_k; - pte_t *pte_k; - - pgd_paddr = read_cr3(); - pgd = index + (pgd_t *)__va(pgd_paddr); - pgd_k = init_mm.pgd + index; - - if (!pgd_present(*pgd_k)) - goto no_context; - - /* - * set_pgd(pgd, *pgd_k); here would be useless on PAE - * and redundant with the set_pmd() on non-PAE. As would - * set_pud. - */ +} - pud = pud_offset(pgd, address); - pud_k = pud_offset(pgd_k, address); - if (!pud_present(*pud_k)) - goto no_context; - - pmd = pmd_offset(pud, address); - pmd_k = pmd_offset(pud_k, address); - if (!pmd_present(*pmd_k)) - goto no_context; - set_pmd(pmd, *pmd_k); +#ifndef CONFIG_X86_PAE +void vmalloc_sync_all(void) +{ + /* + * Note that races in the updates of insync and start aren't + * problematic: insync can only get set bits added, and updates to + * start are only improving performance (without affecting correctness + * if undone). + */ + static DECLARE_BITMAP(insync, PTRS_PER_PGD); + static unsigned long start = TASK_SIZE; + unsigned long address; - pte_k = pte_offset_kernel(pmd_k, address); - if (!pte_present(*pte_k)) - goto no_context; - return; + BUILD_BUG_ON(TASK_SIZE & ~PGDIR_MASK); + for (address = start; address >= TASK_SIZE; address += PGDIR_SIZE) { + if (!test_bit(pgd_index(address), insync)) { + unsigned long flags; + struct page *page; + + spin_lock_irqsave(&pgd_lock, flags); + for (page = pgd_list; page; page = + (struct page *)page->index) + if (!vmalloc_sync_one(page_address(page), + address)) { + BUG_ON(page != pgd_list); + break; + } + spin_unlock_irqrestore(&pgd_lock, flags); + if (!page) + set_bit(pgd_index(address), insync); + } + if (address == start && test_bit(pgd_index(address), insync)) + start = address + PGDIR_SIZE; } } +#endif diff --git a/arch/i386/mm/hugetlbpage.c b/arch/i386/mm/hugetlbpage.c index d524127c9afc..a7d891585411 100644 --- a/arch/i386/mm/hugetlbpage.c +++ b/arch/i386/mm/hugetlbpage.c @@ -48,18 +48,6 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) return (pte_t *) pmd; } -/* - * This function checks for proper alignment of input addr and len parameters. - */ -int is_aligned_hugepage_range(unsigned long addr, unsigned long len) -{ - if (len & ~HPAGE_MASK) - return -EINVAL; - if (addr & ~HPAGE_MASK) - return -EINVAL; - return 0; -} - #if 0 /* This is just for testing */ struct page * follow_huge_addr(struct mm_struct *mm, unsigned long address, int write) diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c index 2700f01994ba..9f66ac582a8b 100644 --- a/arch/i386/mm/init.c +++ b/arch/i386/mm/init.c @@ -270,7 +270,7 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base) static void __meminit free_new_highpage(struct page *page) { - set_page_count(page, 1); + init_page_count(page); __free_page(page); totalhigh_pages++; } @@ -720,21 +720,6 @@ static int noinline do_test_wp_bit(void) return flag; } -void free_initmem(void) -{ - unsigned long addr; - - addr = (unsigned long)(&__init_begin); - for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { - ClearPageReserved(virt_to_page(addr)); - set_page_count(virt_to_page(addr), 1); - memset((void *)addr, 0xcc, PAGE_SIZE); - free_page(addr); - totalram_pages++; - } - printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", (__init_end - __init_begin) >> 10); -} - #ifdef CONFIG_DEBUG_RODATA extern char __start_rodata, __end_rodata; @@ -758,17 +743,31 @@ void mark_rodata_ro(void) } #endif +void free_init_pages(char *what, unsigned long begin, unsigned long end) +{ + unsigned long addr; + + for (addr = begin; addr < end; addr += PAGE_SIZE) { + ClearPageReserved(virt_to_page(addr)); + init_page_count(virt_to_page(addr)); + memset((void *)addr, 0xcc, PAGE_SIZE); + free_page(addr); + totalram_pages++; + } + printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); +} + +void free_initmem(void) +{ + free_init_pages("unused kernel memory", + (unsigned long)(&__init_begin), + (unsigned long)(&__init_end)); +} #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { - if (start < end) - printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10); - for (; start < end; start += PAGE_SIZE) { - ClearPageReserved(virt_to_page(start)); - set_page_count(virt_to_page(start), 1); - free_page(start); - totalram_pages++; - } + free_init_pages("initrd memory", start, end); } #endif + diff --git a/arch/i386/mm/pageattr.c b/arch/i386/mm/pageattr.c index d0cadb33b54c..92c3d9f0e731 100644 --- a/arch/i386/mm/pageattr.c +++ b/arch/i386/mm/pageattr.c @@ -51,6 +51,13 @@ static struct page *split_large_page(unsigned long address, pgprot_t prot, if (!base) return NULL; + /* + * page_private is used to track the number of entries in + * the page table page that have non standard attributes. + */ + SetPagePrivate(base); + page_private(base) = 0; + address = __pa(address); addr = address & LARGE_PAGE_MASK; pbase = (pte_t *)page_address(base); @@ -143,11 +150,12 @@ __change_page_attr(struct page *page, pgprot_t prot) return -ENOMEM; set_pmd_pte(kpte,address,mk_pte(split, ref_prot)); kpte_page = split; - } - get_page(kpte_page); + } + page_private(kpte_page)++; } else if ((pte_val(*kpte) & _PAGE_PSE) == 0) { set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL)); - __put_page(kpte_page); + BUG_ON(page_private(kpte_page) == 0); + page_private(kpte_page)--; } else BUG(); @@ -157,10 +165,8 @@ __change_page_attr(struct page *page, pgprot_t prot) * replace it with a largepage. */ if (!PageReserved(kpte_page)) { - /* memleak and potential failed 2M page regeneration */ - BUG_ON(!page_count(kpte_page)); - - if (cpu_has_pse && (page_count(kpte_page) == 1)) { + if (cpu_has_pse && (page_private(kpte_page) == 0)) { + ClearPagePrivate(kpte_page); list_add(&kpte_page->lru, &df_list); revert_page(kpte_page, address); } diff --git a/arch/i386/mm/pgtable.c b/arch/i386/mm/pgtable.c index 9db3242103be..2889567e21a1 100644 --- a/arch/i386/mm/pgtable.c +++ b/arch/i386/mm/pgtable.c @@ -36,7 +36,7 @@ void show_mem(void) printk(KERN_INFO "Mem-info:\n"); show_free_areas(); printk(KERN_INFO "Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); - for_each_pgdat(pgdat) { + for_each_online_pgdat(pgdat) { pgdat_resize_lock(pgdat, &flags); for (i = 0; i < pgdat->node_spanned_pages; ++i) { page = pgdat_page_nr(pgdat, i); |