IB/hfi1: Fix sleep inside atomic issue in init_asic_data

The critical section should protect only the list traversal
and dd->asic_data modification, not the memory allocation.
The fix pulls the allocation out of the critical section.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index f5de85178055..dad4d0ebbdff 100644
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -14113,8 +14113,14 @@ static int init_asic_data(struct hfi1_devdata *dd)
 {
         unsigned long flags;
         struct hfi1_devdata *tmp, *peer = NULL;
+        struct hfi1_asic_data *asic_data;
         int ret = 0;
 
+        /* pre-allocate the asic structure in case we are the first device */
+        asic_data = kzalloc(sizeof(*dd->asic_data), GFP_KERNEL);
+        if (!asic_data)
+                return -ENOMEM;
+
         spin_lock_irqsave(&hfi1_devs_lock, flags);
         /* Find our peer device */
         list_for_each_entry(tmp, &hfi1_dev_list, list) {
@@ -14126,18 +14132,14 @@ static int init_asic_data(struct hfi1_devdata *dd)
         }
 
         if (peer) {
+                /* use already allocated structure */
                 dd->asic_data = peer->asic_data;
+                kfree(asic_data);
         } else {
-                dd->asic_data = kzalloc(sizeof(*dd->asic_data), GFP_KERNEL);
-                if (!dd->asic_data) {
-                        ret = -ENOMEM;
-                        goto done;
-                }
+                dd->asic_data = asic_data;
                 mutex_init(&dd->asic_data->asic_resource_mutex);
         }
         dd->asic_data->dds[dd->hfi1_id] = dd; /* self back-pointer */
-
-done:
         spin_unlock_irqrestore(&hfi1_devs_lock, flags);
         return ret;
 }