diff options
Diffstat (limited to 'arch/x86/mm/fault.c')
| -rw-r--r-- | arch/x86/mm/fault.c | 62 |
1 files changed, 31 insertions, 31 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index e4440d0abf81..621afb6343dc 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -240,7 +240,8 @@ void dump_pagetable(unsigned long address) pud = pud_offset(pgd, address); if (bad_address(pud)) goto bad; printk("PUD %lx ", pud_val(*pud)); - if (!pud_present(*pud)) goto ret; + if (!pud_present(*pud) || pud_large(*pud)) + goto ret; pmd = pmd_offset(pud, address); if (bad_address(pmd)) goto bad; @@ -427,6 +428,16 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs, } #endif +static int spurious_fault_check(unsigned long error_code, pte_t *pte) +{ + if ((error_code & PF_WRITE) && !pte_write(*pte)) + return 0; + if ((error_code & PF_INSTR) && !pte_exec(*pte)) + return 0; + + return 1; +} + /* * Handle a spurious fault caused by a stale TLB entry. This allows * us to lazily refresh the TLB when increasing the permissions of a @@ -456,20 +467,21 @@ static int spurious_fault(unsigned long address, if (!pud_present(*pud)) return 0; + if (pud_large(*pud)) + return spurious_fault_check(error_code, (pte_t *) pud); + pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) return 0; + if (pmd_large(*pmd)) + return spurious_fault_check(error_code, (pte_t *) pmd); + pte = pte_offset_kernel(pmd, address); if (!pte_present(*pte)) return 0; - if ((error_code & PF_WRITE) && !pte_write(*pte)) - return 0; - if ((error_code & PF_INSTR) && !pte_exec(*pte)) - return 0; - - return 1; + return spurious_fault_check(error_code, pte); } /* @@ -508,6 +520,10 @@ static int vmalloc_fault(unsigned long address) pmd_t *pmd, *pmd_ref; pte_t *pte, *pte_ref; + /* Make sure we are in vmalloc area */ + if (!(address >= VMALLOC_START && address < VMALLOC_END)) + return -1; + /* Copy kernel mappings over when needed. This can also happen within a race in page table update. In the later case just flush. */ @@ -603,6 +619,9 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) */ #ifdef CONFIG_X86_32 if (unlikely(address >= TASK_SIZE)) { +#else + if (unlikely(address >= TASK_SIZE64)) { +#endif if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) && vmalloc_fault(address) >= 0) return; @@ -618,6 +637,8 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) goto bad_area_nosemaphore; } + +#ifdef CONFIG_X86_32 /* It's safe to allow irq's after cr2 has been saved and the vmalloc fault has been handled. */ if (regs->flags & (X86_EFLAGS_IF|VM_MASK)) @@ -630,28 +651,6 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) if (in_atomic() || !mm) goto bad_area_nosemaphore; #else /* CONFIG_X86_64 */ - if (unlikely(address >= TASK_SIZE64)) { - /* - * Don't check for the module range here: its PML4 - * is always initialized because it's shared with the main - * kernel text. Only vmalloc may need PML4 syncups. - */ - if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) && - ((address >= VMALLOC_START && address < VMALLOC_END))) { - if (vmalloc_fault(address) >= 0) - return; - } - - /* Can handle a stale RO->RW TLB */ - if (spurious_fault(address, error_code)) - return; - - /* - * Don't take the mm semaphore here. If we fixup a prefetch - * fault we could otherwise deadlock. - */ - goto bad_area_nosemaphore; - } if (likely(regs->flags & X86_EFLAGS_IF)) local_irq_enable(); @@ -959,11 +958,12 @@ void vmalloc_sync_all(void) for (address = start; address <= VMALLOC_END; address += PGDIR_SIZE) { if (!test_bit(pgd_index(address), insync)) { const pgd_t *pgd_ref = pgd_offset_k(address); + unsigned long flags; struct page *page; if (pgd_none(*pgd_ref)) continue; - spin_lock(&pgd_lock); + spin_lock_irqsave(&pgd_lock, flags); list_for_each_entry(page, &pgd_list, lru) { pgd_t *pgd; pgd = (pgd_t *)page_address(page) + pgd_index(address); @@ -972,7 +972,7 @@ void vmalloc_sync_all(void) else BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref)); } - spin_unlock(&pgd_lock); + spin_unlock_irqrestore(&pgd_lock, flags); set_bit(pgd_index(address), insync); } if (address == start) |