diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/fault.c | 134 | ||||
| -rw-r--r-- | arch/x86/mm/pti.c | 8 | ||||
| -rw-r--r-- | arch/x86/mm/tlb.c | 37 |
3 files changed, 1 insertions, 178 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 255fc631b042..dffe8e4d3140 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -215,44 +215,6 @@ void arch_sync_kernel_mappings(unsigned long start, unsigned long end) } /* - * 32-bit: - * - * Handle a fault on the vmalloc or module mapping area - */ -static noinline int vmalloc_fault(unsigned long address) -{ - unsigned long pgd_paddr; - pmd_t *pmd_k; - pte_t *pte_k; - - /* Make sure we are in vmalloc area: */ - if (!(address >= VMALLOC_START && address < VMALLOC_END)) - return -1; - - /* - * 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_pa(); - pmd_k = vmalloc_sync_one(__va(pgd_paddr), address); - if (!pmd_k) - return -1; - - if (pmd_large(*pmd_k)) - return 0; - - pte_k = pte_offset_kernel(pmd_k, address); - if (!pte_present(*pte_k)) - return -1; - - return 0; -} -NOKPROBE_SYMBOL(vmalloc_fault); - -/* * Did it hit the DOS screen memory VA from vm86 mode? */ static inline void @@ -316,79 +278,6 @@ out: #else /* CONFIG_X86_64: */ -/* - * 64-bit: - * - * Handle a fault on the vmalloc area - */ -static noinline int vmalloc_fault(unsigned long address) -{ - pgd_t *pgd, *pgd_k; - p4d_t *p4d, *p4d_k; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - /* 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: - */ - pgd = (pgd_t *)__va(read_cr3_pa()) + pgd_index(address); - pgd_k = pgd_offset_k(address); - if (pgd_none(*pgd_k)) - return -1; - - if (pgtable_l5_enabled()) { - if (pgd_none(*pgd)) { - set_pgd(pgd, *pgd_k); - arch_flush_lazy_mmu_mode(); - } else { - BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_k)); - } - } - - /* With 4-level paging, copying happens on the p4d level. */ - p4d = p4d_offset(pgd, address); - p4d_k = p4d_offset(pgd_k, address); - if (p4d_none(*p4d_k)) - return -1; - - if (p4d_none(*p4d) && !pgtable_l5_enabled()) { - set_p4d(p4d, *p4d_k); - arch_flush_lazy_mmu_mode(); - } else { - BUG_ON(p4d_pfn(*p4d) != p4d_pfn(*p4d_k)); - } - - BUILD_BUG_ON(CONFIG_PGTABLE_LEVELS < 4); - - pud = pud_offset(p4d, address); - if (pud_none(*pud)) - return -1; - - if (pud_large(*pud)) - return 0; - - pmd = pmd_offset(pud, address); - if (pmd_none(*pmd)) - return -1; - - if (pmd_large(*pmd)) - return 0; - - pte = pte_offset_kernel(pmd, address); - if (!pte_present(*pte)) - return -1; - - return 0; -} -NOKPROBE_SYMBOL(vmalloc_fault); - #ifdef CONFIG_CPU_SUP_AMD static const char errata93_warning[] = KERN_ERR @@ -1227,29 +1116,6 @@ do_kern_addr_fault(struct pt_regs *regs, unsigned long hw_error_code, */ WARN_ON_ONCE(hw_error_code & X86_PF_PK); - /* - * We can fault-in kernel-space virtual memory on-demand. The - * 'reference' page table is init_mm.pgd. - * - * NOTE! We MUST NOT take any locks for this case. We may - * be in an interrupt or a critical region, and should - * only copy the information from the master page table, - * nothing more. - * - * Before doing this on-demand faulting, ensure that the - * fault is not any of the following: - * 1. A fault on a PTE with a reserved bit set. - * 2. A fault caused by a user-mode access. (Do not demand- - * fault kernel memory due to user-mode accesses). - * 3. A fault caused by a page-level protection violation. - * (A demand fault would be on a non-present page which - * would have X86_PF_PROT==0). - */ - if (!(hw_error_code & (X86_PF_RSVD | X86_PF_USER | X86_PF_PROT))) { - if (vmalloc_fault(address) >= 0) - return; - } - /* Was the fault spurious, caused by lazy TLB invalidation? */ if (spurious_kernel_fault(hw_error_code, address)) return; diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index 843aa10a4cb6..da0fb17a1a36 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -448,13 +448,7 @@ static void __init pti_clone_user_shared(void) * the sp1 and sp2 slots. * * This is done for all possible CPUs during boot to ensure - * that it's propagated to all mms. If we were to add one of - * these mappings during CPU hotplug, we would need to take - * some measure to make sure that every mm that subsequently - * ran on that CPU would have the relevant PGD entry in its - * pagetables. The usual vmalloc_fault() mechanism would not - * work for page faults taken in entry_SYSCALL_64 before RSP - * is set up. + * that it's propagated to all mms. */ unsigned long va = (unsigned long)&per_cpu(cpu_tss_rw, cpu); diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 66f96f21a7b6..f3fe261e5936 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -161,34 +161,6 @@ void switch_mm(struct mm_struct *prev, struct mm_struct *next, local_irq_restore(flags); } -static void sync_current_stack_to_mm(struct mm_struct *mm) -{ - unsigned long sp = current_stack_pointer; - pgd_t *pgd = pgd_offset(mm, sp); - - if (pgtable_l5_enabled()) { - if (unlikely(pgd_none(*pgd))) { - pgd_t *pgd_ref = pgd_offset_k(sp); - - set_pgd(pgd, *pgd_ref); - } - } else { - /* - * "pgd" is faked. The top level entries are "p4d"s, so sync - * the p4d. This compiles to approximately the same code as - * the 5-level case. - */ - p4d_t *p4d = p4d_offset(pgd, sp); - - if (unlikely(p4d_none(*p4d))) { - pgd_t *pgd_ref = pgd_offset_k(sp); - p4d_t *p4d_ref = p4d_offset(pgd_ref, sp); - - set_p4d(p4d, *p4d_ref); - } - } -} - static inline unsigned long mm_mangle_tif_spec_ib(struct task_struct *next) { unsigned long next_tif = task_thread_info(next)->flags; @@ -377,15 +349,6 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, */ cond_ibpb(tsk); - if (IS_ENABLED(CONFIG_VMAP_STACK)) { - /* - * If our current stack is in vmalloc space and isn't - * mapped in the new pgd, we'll double-fault. Forcibly - * map it. - */ - sync_current_stack_to_mm(next); - } - /* * Stop remote flushes for the previous mm. * Skip kernel threads; we never send init_mm TLB flushing IPIs, |