On Mon, 2012-06-25 at 19:46 +0200, Miklos Szeredi wrote: > From: Miklos Szeredi <mszer...@suse.cz> > > Drop the initial reference by fsnotify_init_mark early instead of > audit_tree_freeing_mark() at destroy time. > > In the cases we destroy the mark before we drop the initial reference we need > to > get rid of the get_mark that balances the put_mark in > audit_tree_freeing_mark(). > > Signed-off-by: Miklos Szeredi <mszer...@suse.cz>
I don't love this. The reference from fsnotify_init_mark() should live until fsnotify_mark_destroy(). If we need to drop a reference in audit_tree_freeing_mark() we should be taking that elsewhere.... > --- > kernel/audit_tree.c | 12 +++++++++--- > 1 files changed, 9 insertions(+), 3 deletions(-) > > diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c > index 31fdc48..7b95706 100644 > --- a/kernel/audit_tree.c > +++ b/kernel/audit_tree.c > @@ -292,6 +292,7 @@ static void untag_chunk(struct node *p) > spin_unlock(&hash_lock); > spin_unlock(&entry->lock); > fsnotify_destroy_mark(entry); > + fsnotify_put_mark(&new->mark); /* drop initial reference */ > goto out; > > Fallback: > @@ -330,7 +331,6 @@ static int create_chunk(struct inode *inode, struct > audit_tree *tree) > spin_unlock(&hash_lock); > chunk->dead = 1; > spin_unlock(&entry->lock); > - fsnotify_get_mark(entry); > fsnotify_destroy_mark(entry); > fsnotify_put_mark(entry); > return 0; > @@ -346,6 +346,7 @@ static int create_chunk(struct inode *inode, struct > audit_tree *tree) > insert_hash(chunk); > spin_unlock(&hash_lock); > spin_unlock(&entry->lock); > + fsnotify_put_mark(entry); /* drop initial reference */ > return 0; > } > > @@ -411,7 +412,6 @@ static int tag_chunk(struct inode *inode, struct > audit_tree *tree) > spin_unlock(&chunk_entry->lock); > spin_unlock(&old_entry->lock); > > - fsnotify_get_mark(chunk_entry); > fsnotify_destroy_mark(chunk_entry); > > fsnotify_put_mark(chunk_entry); > @@ -444,6 +444,7 @@ static int tag_chunk(struct inode *inode, struct > audit_tree *tree) > spin_unlock(&chunk_entry->lock); > spin_unlock(&old_entry->lock); > fsnotify_destroy_mark(old_entry); > + fsnotify_put_mark(chunk_entry); /* drop initial reference */ > fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ > return 0; > } > @@ -915,7 +916,12 @@ static void audit_tree_freeing_mark(struct fsnotify_mark > *entry, struct fsnotify > struct audit_chunk *chunk = container_of(entry, struct audit_chunk, > mark); > > evict_chunk(chunk); > - fsnotify_put_mark(entry); > + > + /* > + * We are guaranteed to have at least one reference to the mark from > + * either the inode or the caller of fsnotify_destroy_mark(). > + */ > + BUG_ON(atomic_read(&entry->refcnt) < 1); > } > > static bool audit_tree_send_event(struct fsnotify_group *group, struct inode > *inode, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
