This patch avoids that sparse complains about RCU pointer dereferences.

Signed-off-by: Bart Van Assche <bart.vanass...@sandisk.com>
Cc: Hannes Reinecke <h...@suse.de>
Cc: tang.junhui <tang.jun...@zte.com.cn>
Cc: <sta...@vger.kernel.org>
---
 drivers/scsi/device_handler/scsi_dh_alua.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c 
b/drivers/scsi/device_handler/scsi_dh_alua.c
index 7bb2068..815e648 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -95,7 +95,7 @@ struct alua_port_group {
 
 struct alua_dh_data {
        struct list_head        node;
-       struct alua_port_group  *pg;
+       struct alua_port_group __rcu *pg;
        int                     group_id;
        spinlock_t              pg_lock;
        struct scsi_device      *sdev;
@@ -369,7 +369,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct 
alua_dh_data *h,
 
        /* Check for existing port group references */
        spin_lock(&h->pg_lock);
-       old_pg = h->pg;
+       old_pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock));
        if (old_pg != pg) {
                /* port group has changed. Update to new port group */
                if (h->pg) {
@@ -388,7 +388,9 @@ static int alua_check_vpd(struct scsi_device *sdev, struct 
alua_dh_data *h,
                list_add_rcu(&h->node, &pg->dh_list);
        spin_unlock_irqrestore(&pg->lock, flags);
 
-       alua_rtpg_queue(h->pg, sdev, NULL, true);
+       alua_rtpg_queue(rcu_dereference_protected(h->pg,
+                                                 lockdep_is_held(&h->pg_lock)),
+                       sdev, NULL, true);
        spin_unlock(&h->pg_lock);
 
        if (old_pg)
@@ -940,7 +942,7 @@ static int alua_initialize(struct scsi_device *sdev, struct 
alua_dh_data *h)
 static int alua_set_params(struct scsi_device *sdev, const char *params)
 {
        struct alua_dh_data *h = sdev->handler_data;
-       struct alua_port_group __rcu *pg = NULL;
+       struct alua_port_group *pg = NULL;
        unsigned int optimize = 0, argc;
        const char *p = params;
        int result = SCSI_DH_OK;
@@ -987,7 +989,7 @@ static int alua_activate(struct scsi_device *sdev,
        struct alua_dh_data *h = sdev->handler_data;
        int err = SCSI_DH_OK;
        struct alua_queue_data *qdata;
-       struct alua_port_group __rcu *pg;
+       struct alua_port_group *pg;
 
        qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
        if (!qdata) {
@@ -1051,7 +1053,7 @@ static void alua_check(struct scsi_device *sdev, bool 
force)
 static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
 {
        struct alua_dh_data *h = sdev->handler_data;
-       struct alua_port_group __rcu *pg;
+       struct alua_port_group *pg;
        unsigned char state = SCSI_ACCESS_STATE_OPTIMAL;
        int ret = BLKPREP_OK;
 
@@ -1121,7 +1123,7 @@ static void alua_bus_detach(struct scsi_device *sdev)
        struct alua_port_group *pg;
 
        spin_lock(&h->pg_lock);
-       pg = h->pg;
+       pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock));
        rcu_assign_pointer(h->pg, NULL);
        h->sdev = NULL;
        spin_unlock(&h->pg_lock);
-- 
2.10.2

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