From: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx> Subject: ipc/sem.c: convert to use built-in RCU list checking CONFIG_PROVE_RCU_LIST requires list_for_each_entry_rcu() to pass a lockdep expression if using srcu or locking for protection. It can only check regular RCU protection, all other protection needs to be passed as lockdep expression. Link: http://lkml.kernel.org/r/20190830231817.76862-2-joel@xxxxxxxxxxxxxxxxx Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx> Cc: Jonathan Derrick <jonathan.derrick@xxxxxxxxx> Cc: Keith Busch <keith.busch@xxxxxxxxx> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- ipc/sem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/ipc/sem.c~ipc-sem-convert-to-use-built-in-rcu-list-checking +++ a/ipc/sem.c @@ -1852,7 +1852,8 @@ static struct sem_undo *__lookup_undo(st { struct sem_undo *un; - list_for_each_entry_rcu(un, &ulp->list_proc, list_proc) { + list_for_each_entry_rcu(un, &ulp->list_proc, list_proc, + spin_is_locked(&ulp->lock)) { if (un->semid == semid) return un; } _
