[PATCH 4.4 172/342] drm/amdgpu: Fix off-by-one errors in amdgpu_vm_bo_map

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Felix Kuehling <Felix.Kuehling@xxxxxxx>

commit 005ae95e6ec119c64e2d16eb65a94c49e1dcf9f0 upstream.

eaddr is sometimes treated as the last address inside the address
range, and sometimes as the first address outside the range. This
was resulting in errors when a test filled up the entire address
space. Make it consistent to always be the last address within the
range.

Signed-off-by: Felix.Kuehling <Felix.Kuehling@xxxxxxx>
Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1010,13 +1010,13 @@ int amdgpu_vm_bo_map(struct amdgpu_devic
 		return -EINVAL;
 
 	/* make sure object fit at this offset */
-	eaddr = saddr + size;
+	eaddr = saddr + size - 1;
 	if ((saddr >= eaddr) || (offset + size > amdgpu_bo_size(bo_va->bo)))
 		return -EINVAL;
 
 	last_pfn = eaddr / AMDGPU_GPU_PAGE_SIZE;
-	if (last_pfn > adev->vm_manager.max_pfn) {
-		dev_err(adev->dev, "va above limit (0x%08X > 0x%08X)\n",
+	if (last_pfn >= adev->vm_manager.max_pfn) {
+		dev_err(adev->dev, "va above limit (0x%08X >= 0x%08X)\n",
 			last_pfn, adev->vm_manager.max_pfn);
 		return -EINVAL;
 	}
@@ -1025,7 +1025,7 @@ int amdgpu_vm_bo_map(struct amdgpu_devic
 	eaddr /= AMDGPU_GPU_PAGE_SIZE;
 
 	spin_lock(&vm->it_lock);
-	it = interval_tree_iter_first(&vm->va, saddr, eaddr - 1);
+	it = interval_tree_iter_first(&vm->va, saddr, eaddr);
 	spin_unlock(&vm->it_lock);
 	if (it) {
 		struct amdgpu_bo_va_mapping *tmp;
@@ -1046,7 +1046,7 @@ int amdgpu_vm_bo_map(struct amdgpu_devic
 
 	INIT_LIST_HEAD(&mapping->list);
 	mapping->it.start = saddr;
-	mapping->it.last = eaddr - 1;
+	mapping->it.last = eaddr;
 	mapping->offset = offset;
 	mapping->flags = flags;