1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_gart.c b/drivers/gpu/drm/radeon/radeon_gart.c
index 59d44937dd9f..84b648a7ddd8 100644
--- a/drivers/gpu/drm/radeon/radeon_gart.c
+++ b/drivers/gpu/drm/radeon/radeon_gart.c
@@ -289,8 +289,9 @@ int radeon_vm_manager_init(struct radeon_device *rdev)
         rdev->vm_manager.enabled = false;
 
         /* mark first vm as always in use, it's the system one */
+        /* allocate enough for 2 full VM pts */
         r = radeon_sa_bo_manager_init(rdev, &rdev->vm_manager.sa_manager,
-                                      rdev->vm_manager.max_pfn * 8,
+                                      rdev->vm_manager.max_pfn * 8 * 2,
                                       RADEON_GEM_DOMAIN_VRAM);
         if (r) {
                 dev_err(rdev->dev, "failed to allocate vm bo (%dKB)\n",
@@ -633,7 +634,15 @@ int radeon_vm_init(struct radeon_device *rdev, struct radeon_vm *vm)
         mutex_init(&vm->mutex);
         INIT_LIST_HEAD(&vm->list);
         INIT_LIST_HEAD(&vm->va);
-        vm->last_pfn = 0;
+        /* SI requires equal sized PTs for all VMs, so always set
+         * last_pfn to max_pfn.  cayman allows variable sized
+         * pts so we can grow then as needed.  Once we switch
+         * to two level pts we can unify this again.
+         */
+        if (rdev->family >= CHIP_TAHITI)
+                vm->last_pfn = rdev->vm_manager.max_pfn;
+        else
+                vm->last_pfn = 0;
         /* map the ib pool buffer at 0 in virtual address space, set
          * read only
          */