4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Feras Daoud <ferasda@xxxxxxxxxxxx>
[ Upstream commit c586071d1dc8227a7182179b8e50ee92cc43f6d2 ]
In order to resolve a situation where a few process delete
the same list element in sequence and cause panic, list_del
is replaced with list_del_init. In this case if the first
process that calls list_del releases the lock before acquiring
it again, other processes who can acquire the lock will call
list_del_init.
Fixes: b63b70d87741 ("IPoIB: Use a private hash table for path lookup")
Signed-off-by: Feras Daoud <ferasda@xxxxxxxxxxxx>
Signed-off-by: Erez Shitrit <erezsh@xxxxxxxxxxxx>
Reviewed-by: Alex Vesker <valex@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Reviewed-by: Yuval Shaia <yuval.shaia@xxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/ulp/ipoib/ipoib_main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1239,7 +1239,7 @@ static void __ipoib_reap_neigh(struct ip
rcu_dereference_protected(neigh->hnext,
lockdep_is_held(&priv->lock)));
/* remove from path/mc list */
- list_del(&neigh->list);
+ list_del_init(&neigh->list);
call_rcu(&neigh->rcu, ipoib_neigh_reclaim);
} else {
np = &neigh->hnext;
@@ -1406,7 +1406,7 @@ void ipoib_neigh_free(struct ipoib_neigh
rcu_dereference_protected(neigh->hnext,
lockdep_is_held(&priv->lock)));
/* remove from parent list */
- list_del(&neigh->list);
+ list_del_init(&neigh->list);
call_rcu(&neigh->rcu, ipoib_neigh_reclaim);
return;
} else {
@@ -1491,7 +1491,7 @@ void ipoib_del_neighs_by_gid(struct net_
rcu_dereference_protected(neigh->hnext,
lockdep_is_held(&priv->lock)));
/* remove from parent list */
- list_del(&neigh->list);
+ list_del_init(&neigh->list);
call_rcu(&neigh->rcu, ipoib_neigh_reclaim);
} else {
np = &neigh->hnext;
@@ -1533,7 +1533,7 @@ static void ipoib_flush_neighs(struct ip
rcu_dereference_protected(neigh->hnext,
lockdep_is_held(&priv->lock)));
/* remove from path/mc list */
- list_del(&neigh->list);
+ list_del_init(&neigh->list);
call_rcu(&neigh->rcu, ipoib_neigh_reclaim);
}
}