2 files changed, 6 insertions, 47 deletions

diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c
index 7c507fb48182..f49fd873df8d 100644
--- a/arch/powerpc/mm/copro_fault.c
+++ b/arch/powerpc/mm/copro_fault.c
@@ -33,19 +33,11 @@ int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
 	if (mm->pgd == NULL)
 		return -EFAULT;
 
-	mmap_read_lock(mm);
-	ret = -EFAULT;
-	vma = find_vma(mm, ea);
+	vma = lock_mm_and_find_vma(mm, ea, NULL);
 	if (!vma)
-		goto out_unlock;
-
-	if (ea < vma->vm_start) {
-		if (!(vma->vm_flags & VM_GROWSDOWN))
-			goto out_unlock;
-		if (expand_stack(vma, ea))
-			goto out_unlock;
-	}
+		return -EFAULT;
 
+	ret = -EFAULT;
 	is_write = dsisr & DSISR_ISSTORE;
 	if (is_write) {
 		if (!(vma->vm_flags & VM_WRITE))
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 531177a4ee08..5bfdf6ecfa96 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -84,11 +84,6 @@ static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code)
 	return __bad_area_nosemaphore(regs, address, si_code);
 }
 
-static noinline int bad_area(struct pt_regs *regs, unsigned long address)
-{
-	return __bad_area(regs, address, SEGV_MAPERR);
-}
-
 static noinline int bad_access_pkey(struct pt_regs *regs, unsigned long address,
 				    struct vm_area_struct *vma)
 {
@@ -515,40 +510,12 @@ lock_mmap:
 	 * we will deadlock attempting to validate the fault against the
 	 * address space.  Luckily the kernel only validly references user
 	 * space from well defined areas of code, which are listed in the
-	 * exceptions table.
-	 *
-	 * As the vast majority of faults will be valid we will only perform
-	 * the source reference check when there is a possibility of a deadlock.
-	 * Attempt to lock the address space, if we cannot we then validate the
-	 * source.  If this is invalid we can skip the address space check,
-	 * thus avoiding the deadlock.
+	 * exceptions table. lock_mm_and_find_vma() handles that logic.
 	 */
-	if (unlikely(!mmap_read_trylock(mm))) {
-		if (!is_user && !search_exception_tables(regs->nip))
-			return bad_area_nosemaphore(regs, address);
-
 retry:
-		mmap_read_lock(mm);
-	} else {
-		/*
-		 * The above down_read_trylock() might have succeeded in
-		 * which case we'll have missed the might_sleep() from
-		 * down_read():
-		 */
-		might_sleep();
-	}
-
-	vma = find_vma(mm, address);
+	vma = lock_mm_and_find_vma(mm, address, regs);
 	if (unlikely(!vma))
-		return bad_area(regs, address);
-
-	if (unlikely(vma->vm_start > address)) {
-		if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)))
-			return bad_area(regs, address);
-
-		if (unlikely(expand_stack(vma, address)))
-			return bad_area(regs, address);
-	}
+		return bad_area_nosemaphore(regs, address);
 
 	if (unlikely(access_pkey_error(is_write, is_exec,
 				       (error_code & DSISR_KEYFAULT), vma)))