[PATCH net-next 0/2] tipc: eliminate smatch warnings

[PATCH net-next 0/2] tipc: eliminate smatch warnings

[Jon Maloy]

We fix a couple of issues introduced by the series 
"tipc: clean up media and bearer layer". 

Thanks to Dan Carpenter and Walter Harms for highlighting this.

Jon Maloy (2):
  tipc: fix a loop style problem
  tipc: correct usage of spin_lock() vs spin_lock_bh()

 net/tipc/link.c |    6 +++---
 net/tipc/node.c |   10 +++++-----
 2 files changed, 8 insertions(+), 8 deletions(-)

-- 
1.7.9.5

[PATCH net-next 1/2] tipc: fix a loop style problem

[Jon Maloy]

In commit 7d33939f475d403e79124e3143d7951dcfe8629f
("tipc: delay delete of link when failover is needed") we
introduced a loop for finding and removing a link pointer
in an array. The removal is done after we have left the loop,
giving the impression that one may remove the wrong pointer
if no matching element is found.

This is not really a bug, since we know that there will always
be a matching element, but it looks wrong, and causes a smatch
warning.

We fix this loop with this commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/node.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/tipc/node.c b/net/tipc/node.c
index 833324b..8596880 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -252,12 +252,12 @@ void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
 	int i;
 
 	for (i = 0; i < MAX_BEARERS; i++) {
-		if (l_ptr == n_ptr->links[i])
-			break;
+		if (l_ptr != n_ptr->links[i])
+			continue;
+		n_ptr->links[i] = NULL;
+		atomic_dec(&tipc_num_links);
+		n_ptr->link_cnt--;
 	}
-	n_ptr->links[i] = NULL;
-	atomic_dec(&tipc_num_links);
-	n_ptr->link_cnt--;
 }
 
 static void node_established_contact(struct tipc_node *n_ptr)
-- 
1.7.9.5

[PATCH net-next 2/2] tipc: correct usage of spin_lock() vs spin_lock_bh()

[Jon Maloy]

I commit e099e86c9e24fe9aff36773600543eb31d8954d
("tipc: add node_lock protection to link lookup function")
we are calling spin_lock(&node->lock) directly instead of indirectly
via the tipc_node_lock(node) function. However, tipc_node_lock() is
using spin_lock_bh(), not spin_lock(), something leading to
unbalanced usage in one place, and a smatch warning.

We fix this by consistently using tipc_node_lock()/unlock() in
in the places touched by the mentioned commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
---
 net/tipc/link.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 4fb4ae0..5422e96 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -2410,7 +2410,7 @@ static struct tipc_node *tipc_link_find_owner(const char *link_name,
 
 	*bearer_id = 0;
 	list_for_each_entry_safe(n_ptr, tmp_n_ptr, &tipc_node_list, list) {
-		spin_lock(&n_ptr->lock);
+		tipc_node_lock(n_ptr);
 		for (i = 0; i < MAX_BEARERS; i++) {
 			l_ptr = n_ptr->links[i];
 			if (l_ptr && !strcmp(l_ptr->name, link_name)) {
@@ -2419,7 +2419,7 @@ static struct tipc_node *tipc_link_find_owner(const char *link_name,
 				break;
 			}
 		}
-		spin_unlock(&n_ptr->lock);
+		tipc_node_unlock(n_ptr);
 		if (found_node)
 			break;
 	}
@@ -2603,7 +2603,7 @@ struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_
 		read_unlock_bh(&tipc_net_lock);
 		return tipc_cfg_reply_error_string("link not found");
 	}
-	spin_lock(&node->lock);
+	tipc_node_lock(node);
 	l_ptr = node->links[bearer_id];
 	if (!l_ptr) {
 		tipc_node_unlock(node);
-- 
1.7.9.5

Re: [PATCH net-next 0/2] tipc: eliminate smatch warnings

[David Miller]

From: Jon Maloy <jon.maloy@ericsson.com>
Date: Fri, 14 Feb 2014 16:40:42 -0500

> We fix a couple of issues introduced by the series 
> "tipc: clean up media and bearer layer". 
> 
> Thanks to Dan Carpenter and Walter Harms for highlighting this.

Both patches applied, thanks.

------------------------------------------------------------------------------
Android apps run on BlackBerry 10
Introducing the new BlackBerry 10.2.1 Runtime for Android apps.
Now with support for Jelly Bean, Bluetooth, Mapview and more.
Get your Android app in front of a whole new audience.  Start now.
http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk