Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: fix compat-vdso
  x86/mm: unify init task OOM handling
  x86/mm: do not trigger a kernel warning if user-space disables interrupts and generates a page fault

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 3f2b8962cbd0f71223ed8dfed8f90b893a966349..31e8730fa2463214f36c2f6b3df9d0f75f6be346 100644 (file)
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -640,24 +640,23 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
        }
 
 
-#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 | X86_VM_MASK))
-               local_irq_enable();
-
        /*
-        * If we're in an interrupt, have no user context or are running in an
-        * atomic region then we must not take the fault.
+        * It's safe to allow irq's after cr2 has been saved and the
+        * vmalloc fault has been handled.
+        *
+        * User-mode registers count as a user access even for any
+        * potential system fault or CPU buglet.
         */
-       if (in_atomic() || !mm)
-               goto bad_area_nosemaphore;
-#else /* CONFIG_X86_64 */
-       if (likely(regs->flags & X86_EFLAGS_IF))
+       if (user_mode_vm(regs)) {
+               local_irq_enable();
+               error_code |= PF_USER;
+       } else if (regs->flags & X86_EFLAGS_IF)
                local_irq_enable();
 
+#ifdef CONFIG_X86_64
        if (unlikely(error_code & PF_RSVD))
                pgtable_bad(address, regs, error_code);
+#endif
 
        /*
         * If we're in an interrupt, have no user context or are running in an
@@ -666,15 +665,9 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
        if (unlikely(in_atomic() || !mm))
                goto bad_area_nosemaphore;
 
-       /*
-        * User-mode registers count as a user access even for any
-        * potential system fault or CPU buglet.
-        */
-       if (user_mode_vm(regs))
-               error_code |= PF_USER;
 again:
-#endif
-       /* When running in the kernel we expect faults to occur only to
+       /*
+        * When running in the kernel we expect faults to occur only to
         * addresses in user space.  All other faults represent errors in the
         * kernel and should generate an OOPS.  Unfortunately, in the case of an
         * erroneous fault occurring in a code path which already holds mmap_sem
@@ -737,9 +730,6 @@ good_area:
                        goto bad_area;
        }
 
-#ifdef CONFIG_X86_32
-survive:
-#endif
        /*
         * If for any reason at all we couldn't handle the fault,
         * make sure we exit gracefully rather than endlessly redo
@@ -874,12 +864,11 @@ out_of_memory:
        up_read(&mm->mmap_sem);
        if (is_global_init(tsk)) {
                yield();
-#ifdef CONFIG_X86_32
-               down_read(&mm->mmap_sem);
-               goto survive;
-#else
+               /*
+                * Re-lookup the vma - in theory the vma tree might
+                * have changed:
+                */
                goto again;
-#endif
        }
 
        printk("VM: killing process %s\n", tsk->comm);

diff --git a/include/asm-x86/pgtable.h b/include/asm-x86/pgtable.h
index 182f9d4c570f5e9f33d3cd5b1b161a37d313fe36..88a53b1a17f03f486e9a22a138b30b2e422e6544 100644 (file)
--- a/include/asm-x86/pgtable.h
+++ b/include/asm-x86/pgtable.h
@@ -148,8 +148,13 @@
 #ifdef CONFIG_X86_64
 #define __PAGE_KERNEL_IDENT_LARGE_EXEC __PAGE_KERNEL_LARGE_EXEC
 #else
+/*
+ * For PDE_IDENT_ATTR include USER bit. As the PDE and PTE protection
+ * bits are combined, this will alow user to access the high address mapped
+ * VDSO in the presence of CONFIG_COMPAT_VDSO
+ */
 #define PTE_IDENT_ATTR  0x003          /* PRESENT+RW */
-#define PDE_IDENT_ATTR  0x063          /* PRESENT+RW+DIRTY+ACCESSED */
+#define PDE_IDENT_ATTR  0x067          /* PRESENT+RW+USER+DIRTY+ACCESSED */
 #define PGD_IDENT_ATTR  0x001          /* PRESENT (no other attributes) */
 #endif