Commit 454ed842 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

lockdep: annotate mm_take_all_locks() 



The nesting is correct due to holding mmap_sem, use the new annotation
to annotate this.

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b7d39aff

mm/mmap.c

+6 −6
Original line number Diff line number Diff line
@@ -2273,14 +2273,14 @@ int install_special_mapping(struct mm_struct *mm, 


static DEFINE_MUTEX(mm_all_locks_mutex);



static void vm_lock_anon_vma(struct anon_vma *anon_vma)

static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma)

{

	if (!test_bit(0, (unsigned long *) &anon_vma->head.next)) {

		/*

		 * The LSB of head.next can't change from under us

		 * because we hold the mm_all_locks_mutex.

		 */

		spin_lock(&anon_vma->lock);

		spin_lock_nest_lock(&anon_vma->lock, &mm->mmap_sem);

		/*

		 * We can safely modify head.next after taking the

		 * anon_vma->lock. If some other vma in this mm shares
@@ -2296,7 +2296,7 @@ static void vm_lock_anon_vma(struct anon_vma *anon_vma) 
	}

}



static void vm_lock_mapping(struct address_space *mapping)

static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)

{

	if (!test_bit(AS_MM_ALL_LOCKS, &mapping->flags)) {

		/*
@@ -2310,7 +2310,7 @@ static void vm_lock_mapping(struct address_space *mapping) 
		 */

		if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags))

			BUG();

		spin_lock(&mapping->i_mmap_lock);

		spin_lock_nest_lock(&mapping->i_mmap_lock, &mm->mmap_sem);

	}

}
@@ -2359,9 +2359,9 @@ int mm_take_all_locks(struct mm_struct *mm) 
		if (signal_pending(current))

			goto out_unlock;

		if (vma->anon_vma)

			vm_lock_anon_vma(vma->anon_vma);

			vm_lock_anon_vma(mm, vma->anon_vma);

		if (vma->vm_file && vma->vm_file->f_mapping)

			vm_lock_mapping(vma->vm_file->f_mapping);

			vm_lock_mapping(mm, vma->vm_file->f_mapping);

	}

	ret = 0;