IB/ehca: Fix locking for shca_list_lock

shca_list_lock is taken from softirq context in ehca_poll_eqs, so we
need to lock IRQ safe elsewhere.  Found by lockdep.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 10 insertions, 7 deletions

diff --git a/drivers/infiniband/hw/ehca/ehca_main.c b/drivers/infiniband/hw/ehca/ehca_main.c
index bec7e024935..3b77b674cbf 100644
--- a/drivers/infiniband/hw/ehca/ehca_main.c
+++ b/drivers/infiniband/hw/ehca/ehca_main.c
@@ -717,6 +717,7 @@ static int __devinit ehca_probe(struct of_device *dev,
         const u64 *handle;
         struct ib_pd *ibpd;
         int ret, i, eq_size;
+        unsigned long flags;
 
         handle = of_get_property(dev->node, "ibm,hca-handle", NULL);
         if (!handle) {
@@ -830,9 +831,9 @@ static int __devinit ehca_probe(struct of_device *dev,
                 ehca_err(&shca->ib_device,
                          "Cannot create device attributes  ret=%d", ret);
 
-        spin_lock(&shca_list_lock);
+        spin_lock_irqsave(&shca_list_lock, flags);
         list_add(&shca->shca_list, &shca_list);
-        spin_unlock(&shca_list_lock);
+        spin_unlock_irqrestore(&shca_list_lock, flags);
 
         return 0;
 
@@ -878,6 +879,7 @@ probe1:
 static int __devexit ehca_remove(struct of_device *dev)
 {
         struct ehca_shca *shca = dev->dev.driver_data;
+        unsigned long flags;
         int ret;
 
         sysfs_remove_group(&dev->dev.kobj, &ehca_dev_attr_grp);
@@ -915,9 +917,9 @@ static int __devexit ehca_remove(struct of_device *dev)
 
         ib_dealloc_device(&shca->ib_device);
 
-        spin_lock(&shca_list_lock);
+        spin_lock_irqsave(&shca_list_lock, flags);
         list_del(&shca->shca_list);
-        spin_unlock(&shca_list_lock);
+        spin_unlock_irqrestore(&shca_list_lock, flags);
 
         return ret;
 }
@@ -975,6 +977,7 @@ static int ehca_mem_notifier(struct notifier_block *nb,
                              unsigned long action, void *data)
 {
         static unsigned long ehca_dmem_warn_time;
+        unsigned long flags;
 
         switch (action) {
         case MEM_CANCEL_OFFLINE:
@@ -985,12 +988,12 @@ static int ehca_mem_notifier(struct notifier_block *nb,
         case MEM_GOING_ONLINE:
         case MEM_GOING_OFFLINE:
                 /* only ok if no hca is attached to the lpar */
-                spin_lock(&shca_list_lock);
+                spin_lock_irqsave(&shca_list_lock, flags);
                 if (list_empty(&shca_list)) {
-                        spin_unlock(&shca_list_lock);
+                        spin_unlock_irqrestore(&shca_list_lock, flags);
                         return NOTIFY_OK;
                 } else {
-                        spin_unlock(&shca_list_lock);
+                        spin_unlock_irqrestore(&shca_list_lock, flags);
                         if (printk_timed_ratelimit(&ehca_dmem_warn_time,
                                                    30 * 1000))
                                 ehca_gen_err("DMEM operations are not allowed"