diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index f0c47dab090..04f7df39ffb 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -182,8 +182,8 @@ static struct page * vdso_vma_nopage(struct vm_area_struct * vma,
 	unsigned long offset = address - vma->vm_start;
 	struct page *pg;
 #ifdef CONFIG_PPC64
-	void *vbase = test_thread_flag(TIF_32BIT) ?
-		vdso32_kbase : vdso64_kbase;
+	void *vbase = (vma->vm_mm->task_size > TASK_SIZE_USER32) ?
+		vdso64_kbase : vdso32_kbase;
 #else
 	void *vbase = vdso32_kbase;
 #endif
diff --git a/fs/exec.c b/fs/exec.c
index 0e1c95074d4..0b515ac5313 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -885,6 +885,12 @@ int flush_old_exec(struct linux_binprm * bprm)
 	current->flags &= ~PF_RANDOMIZE;
 	flush_thread();
 
+	/* Set the new mm task size. We have to do that late because it may
+	 * depend on TIF_32BIT which is only updated in flush_thread() on
+	 * some architectures like powerpc
+	 */
+	current->mm->task_size = TASK_SIZE;
+
 	if (bprm->e_uid != current->euid || bprm->e_gid != current->egid || 
 	    file_permission(bprm->file, MAY_READ) ||
 	    (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)) {
diff --git a/include/linux/sched.h b/include/linux/sched.h
index b6f51e3a38e..ff2e09c953b 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -298,8 +298,9 @@ struct mm_struct {
 				unsigned long addr, unsigned long len,
 				unsigned long pgoff, unsigned long flags);
 	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
-        unsigned long mmap_base;		/* base of mmap area */
-        unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
+	unsigned long mmap_base;		/* base of mmap area */
+	unsigned long task_size;		/* size of task vm space */
+	unsigned long cached_hole_size;         /* if non-zero, the largest hole below free_area_cache */
 	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
 	pgd_t * pgd;
 	atomic_t mm_users;			/* How many users with user space? */