On Fri, Oct 05, 2018 at 09:40:57PM -0700, Joel Fernandes wrote: > > Could you annotate this pointer (sbi->s_qf_names) with __rcu so it can be > checked by sparse for proper usage? Its also point #16 in the checklist.txt > RCU document. I enclosed a diff to do this below. Sure. > I also saw a bunch of places in super.c where the pointer isn't accessed from > an rcu read section or rcu_dereference, but it was a quick look so sorry if I > missed something. If its true, then are you planning to convert these to use > rcu_dereference and wrapped by an rcu_read_lock/unlock as well? These are places where we are holding s_umount, so there's no way s_qf_names can change out from under us. So the conversion should be to use rcu_dereference_protected(). > > + to_free[i] = rcu_dereference_protected(sbi->s_qf_names[i], > > + &sb->s_umount); > > Also should this be the following? > to_free[i] = rcu_dereference_protected(sbi->s_qf_names[i], > lockdep_is_held(&sb->s_umount)); Yep, good catch, thanks. - Ted
