Fix for [Bug #112247] Hard MGA lock with trispd -size 50000

diff --git a/linux/mga_dma.c b/linux/mga_dma.c
index f80fb48..f115d71 100644 (file)
--- a/linux/mga_dma.c
+++ b/linux/mga_dma.c
@@ -214,6 +214,7 @@ drm_buf_t *mga_freelist_get(drm_device_t *dev)
        drm_mga_freelist_t *prev;
        drm_mga_freelist_t *next;
        static int failed = 0;
+       int return_null = 0;
 
        DRM_DEBUG("%s : tail->age : %d last_prim_age : %d\n", __FUNCTION__,
               dev_priv->tail->age, dev_priv->last_prim_age);
@@ -222,7 +223,6 @@ drm_buf_t *mga_freelist_get(drm_device_t *dev)
                DRM_DEBUG("I'm waiting on the freelist!!! %d\n",
                       dev_priv->last_prim_age);
                set_bit(MGA_IN_GETBUF, &dev_priv->dispatch_status);
-               current->state = TASK_INTERRUPTIBLE;
                add_wait_queue(&dev_priv->buf_queue, &entry);
                for (;;) {
                        mga_dma_schedule(dev, 0);
@@ -230,15 +230,18 @@ drm_buf_t *mga_freelist_get(drm_device_t *dev)
                                     &dev_priv->dispatch_status))
                                break;
                        atomic_inc(&dev->total_sleeps);
+                       current->state = TASK_INTERRUPTIBLE;
                        schedule();
                        if (signal_pending(current)) {
+                               DRM_ERROR("Returning NULL\n");
+                               ++return_null;
                                clear_bit(MGA_IN_GETBUF,
                                          &dev_priv->dispatch_status);
-                               goto failed_getbuf;
+                               break;
                        }
                }
-               current->state = TASK_RUNNING;
                remove_wait_queue(&dev_priv->buf_queue, &entry);
+               if (return_null) return NULL;
        }
 
        if(dev_priv->tail->age < dev_priv->last_prim_age) {
@@ -251,8 +254,6 @@ drm_buf_t *mga_freelist_get(drm_device_t *dev)
                failed = 0;
                return next->buf;
        }
-
-failed_getbuf:
        failed++;
        return NULL;
 }