x86/mm: remove vmalloc faulting

[thirdparty/linux.git] / arch / x86 / mm / fault.c

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 255fc631b042d7ec335bfeec77045c2593a38915..dffe8e4d3140efa283c30d75d7eb3552d8ca800c 100644 (file)
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -214,44 +214,6 @@ 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?
  */
@@ -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;