On Sat, 2009-04-18 at 12:11 +0900, hooanon05@xxxxxxxxxxx wrote: > David Woodhouse: > > This patch fixes it by locking the directory's i_mutex again before > > calling the filldir functions. The original deadlocks which commit > > 14f7dd63 was designed to avoid are still avoided, because they were due > > to fs-internal locking, not i_mutex. > ::: > > --- a/fs/namei.c > > +++ b/fs/namei.c > > @@ -1248,6 +1248,8 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) > > int err; > > struct qstr this; > > > > + WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex)); > > + > > err = __lookup_one_len(name, &this, base, len); > > I'd suggest this checking is done only when CONFIG_DEBUG_KERNEL (or > something) is enabled. Because unconditional checking costs high for the > well-reviewed lookup code. It's supposed to be locked. It's likely to have been locked quite recently, so it'll be in the cache. I don't think the mutex_is_locked() check is going to be that expensive, is it? -- David Woodhouse Open Source Technology Centre David.Woodhouse@xxxxxxxxx Intel Corporation -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
