RDMA/rtrs-srv: Replace device_register with device_initialize and device_add

There are error cases when we will call free_srv before device kobject is
initialized; in such cases calling put_device generates the following
warning:

 kobject: '(null)' (000000009f5445ed): is not initialized, yet
 kobject_put() is being called.

So call device_initialize() only once when the server is allocated. If we
end up calling put_srv() and subsequently free_srv(), our call to
put_device() would result in deletion of the obj. Call device_add() later
when we actually have a connection. Correspondingly, call device_del()
instead of device_unregister() when srv->dev_ref falls to 0.

Fixes: 9cb837480424 ("RDMA/rtrs: server: main functionality")
Link: https://lore.kernel.org/r/20200811092722.2450-1-haris.iqbal@cloud.ionos.com
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c b/drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c
index 3d78775..2f981ae 100644 (file)
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c
@@ -182,16 +182,16 @@ static int rtrs_srv_create_once_sysfs_root_folders(struct rtrs_srv_sess *sess)
         * sysfs files are created
         */
        dev_set_uevent_suppress(&srv->dev, true);
-       err = device_register(&srv->dev);
+       err = device_add(&srv->dev);
        if (err) {
-               pr_err("device_register(): %d\n", err);
+               pr_err("device_add(): %d\n", err);
                goto put;
        }
        srv->kobj_paths = kobject_create_and_add("paths", &srv->dev.kobj);
        if (!srv->kobj_paths) {
                err = -ENOMEM;
                pr_err("kobject_create_and_add(): %d\n", err);
-               device_unregister(&srv->dev);
+               device_del(&srv->dev);
                goto unlock;
        }
        dev_set_uevent_suppress(&srv->dev, false);
@@ -216,7 +216,7 @@ rtrs_srv_destroy_once_sysfs_root_folders(struct rtrs_srv_sess *sess)
                kobject_del(srv->kobj_paths);
                kobject_put(srv->kobj_paths);
                mutex_unlock(&srv->paths_mutex);
-               device_unregister(&srv->dev);
+               device_del(&srv->dev);
        } else {
                mutex_unlock(&srv->paths_mutex);
        }

diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
index a219bd1..b61a18e 100644 (file)
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
@@ -1336,6 +1336,7 @@ static struct rtrs_srv *__alloc_srv(struct rtrs_srv_ctx *ctx,
        uuid_copy(&srv->paths_uuid, paths_uuid);
        srv->queue_depth = sess_queue_depth;
        srv->ctx = ctx;
+       device_initialize(&srv->dev);
 
        srv->chunks = kcalloc(srv->queue_depth, sizeof(*srv->chunks),
                              GFP_KERNEL);