On 6/10/2022 5:45 PM, Jiapeng Chong wrote:
This was found by coccicheck:
./drivers/infiniband/core/cm.c:685:7-9: WARNING: possible condition with no effect (if == else).
Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Signed-off-by: Jiapeng Chong <jiapeng.chong@xxxxxxxxxxxxxxxxx>
---
drivers/infiniband/core/cm.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index 1c107d6d03b9..bb6a2b6b9657 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -676,14 +676,9 @@ static struct cm_id_private *cm_find_listen(struct ib_device *device,
refcount_inc(&cm_id_priv->refcount);
return cm_id_priv;
}
- if (device < cm_id_priv->id.device)
+ if (device < cm_id_priv->id.device ||
+ be64_lt(service_id, cm_id_priv->id.service_id))
node = node->rb_left;
- else if (device > cm_id_priv->id.device)
- node = node->rb_right;
- else if (be64_lt(service_id, cm_id_priv->id.service_id))
- node = node->rb_left;
- else if (be64_gt(service_id, cm_id_priv->id.service_id))
- node = node->rb_right;
else
node = node->rb_right;
}
Not sure if the fix is correct, e.g. with this condition:
device > cm_id_priv->id.device &&
be64_lt(service_id, cm_id_priv->id.service_id)
The original code gets rb_right but this fix gets rb_left. Maybe the
warning is complain about this:
...
else if (be64_gt(service_id, cm_id_priv->id.service_id))
node = node->rb_right;
else
node = node->rb_right;
Besides cm_insert_listen() has same logic.
