[ 124/187] tcm_fc: Resolve suspicious RCU usage warnings

Greg Kroah-Hartman
2012-07-12T23:01:57Z

From: Mark Rustad <mark.d.rustad@intel.com>

commit 863555be0c81558b1af277addcf68acb8f778860 upstream.

Use rcu_dereference_protected to tell rcu that the ft_lport_lock
is held during ft_lport_create. This resolved "suspicious RCU usage"
warnings when debugging options are turned on.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/target/tcm_fc/tfc_sess.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/target/tcm_fc/tfc_sess.c
+++ b/drivers/target/tcm_fc/tfc_sess.c
@@ -58,7 +58,8 @@ static struct ft_tport *ft_tport_create(
struct ft_tport *tport;
int i;

- tport = rcu_dereference(lport->prov[FC_TYPE_FCP]);
+ tport = rcu_dereference_protected(lport->prov[FC_TYPE_FCP],
+ lockdep_is_held(&ft_lport_lock));
if (tport && tport->tpg)
return tport;