drm/nouveau: split ramin_lock into two locks, one hardirq safe

Fixes a possible lock ordering reversal between context_switch_lock
and ramin_lock.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_object.c b/drivers/gpu/drm/nouveau/nouveau_object.c
index 4f00c87ed86e..67a16e01ffa6 100644
--- a/drivers/gpu/drm/nouveau/nouveau_object.c
+++ b/drivers/gpu/drm/nouveau/nouveau_object.c
@@ -1039,19 +1039,20 @@ nv_ro32(struct nouveau_gpuobj *gpuobj, u32 offset)
 {
         struct drm_nouveau_private *dev_priv = gpuobj->dev->dev_private;
         struct drm_device *dev = gpuobj->dev;
+        unsigned long flags;
 
         if (gpuobj->pinst == ~0 || !dev_priv->ramin_available) {
                 u64  ptr = gpuobj->vinst + offset;
                 u32 base = ptr >> 16;
                 u32  val;
 
-                spin_lock(&dev_priv->ramin_lock);
+                spin_lock_irqsave(&dev_priv->vm_lock, flags);
                 if (dev_priv->ramin_base != base) {
                         dev_priv->ramin_base = base;
                         nv_wr32(dev, 0x001700, dev_priv->ramin_base);
                 }
                 val = nv_rd32(dev, 0x700000 + (ptr & 0xffff));
-                spin_unlock(&dev_priv->ramin_lock);
+                spin_unlock_irqrestore(&dev_priv->vm_lock, flags);
                 return val;
         }
 
@@ -1063,18 +1064,19 @@ nv_wo32(struct nouveau_gpuobj *gpuobj, u32 offset, u32 val)
 {
         struct drm_nouveau_private *dev_priv = gpuobj->dev->dev_private;
         struct drm_device *dev = gpuobj->dev;
+        unsigned long flags;
 
         if (gpuobj->pinst == ~0 || !dev_priv->ramin_available) {
                 u64  ptr = gpuobj->vinst + offset;
                 u32 base = ptr >> 16;
 
-                spin_lock(&dev_priv->ramin_lock);
+                spin_lock_irqsave(&dev_priv->vm_lock, flags);
                 if (dev_priv->ramin_base != base) {
                         dev_priv->ramin_base = base;
                         nv_wr32(dev, 0x001700, dev_priv->ramin_base);
                 }
                 nv_wr32(dev, 0x700000 + (ptr & 0xffff), val);
-                spin_unlock(&dev_priv->ramin_lock);
+                spin_unlock_irqrestore(&dev_priv->vm_lock, flags);
                 return;
         }