drm/radeon: move IB pool to 1MB offset

Even GPUs can have a null pointer dereference, so move
the IB pool to another offset to catch those.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>

3 files changed, 5 insertions, 4 deletions

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index d48bd3045db6..55f17f9bc095 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -123,6 +123,7 @@ extern int radeon_lockup_timeout;
 #define CAYMAN_RING_TYPE_CP2_INDEX              2
 
 /* hardcode those limit for now */
+#define RADEON_VA_IB_OFFSET                     (1 << 20)
 #define RADEON_VA_RESERVED_SIZE                 (8 << 20)
 #define RADEON_IB_VM_MAX_SIZE                   (64 << 10)
 
diff --git a/drivers/gpu/drm/radeon/radeon_gart.c b/drivers/gpu/drm/radeon/radeon_gart.c
index 5694421b7c67..1b1c001e269a 100644
--- a/drivers/gpu/drm/radeon/radeon_gart.c
+++ b/drivers/gpu/drm/radeon/radeon_gart.c
@@ -980,7 +980,7 @@ int radeon_vm_init(struct radeon_device *rdev, struct radeon_vm *vm)
         /* map the ib pool buffer at 0 in virtual address space, set
          * read only
          */
-        r = radeon_vm_bo_add(rdev, vm, rdev->ring_tmp_bo.bo, 0,
+        r = radeon_vm_bo_add(rdev, vm, rdev->ring_tmp_bo.bo, RADEON_VA_IB_OFFSET,
                              RADEON_VM_PAGE_READABLE | RADEON_VM_PAGE_SNOOPED);
         return r;
 }
diff --git a/drivers/gpu/drm/radeon/radeon_ring.c b/drivers/gpu/drm/radeon/radeon_ring.c
index 993cf712074f..d90b0bc6f072 100644
--- a/drivers/gpu/drm/radeon/radeon_ring.c
+++ b/drivers/gpu/drm/radeon/radeon_ring.c
@@ -79,10 +79,10 @@ int radeon_ib_get(struct radeon_device *rdev, int ring,
         ib->ptr = radeon_sa_bo_cpu_addr(ib->sa_bo);
         ib->vm = vm;
         if (vm) {
-                /* ib pool is bind at 0 in virtual address space,
-                 * so gpu_addr is the offset inside the pool bo
+                /* ib pool is bound at RADEON_VA_IB_OFFSET in virtual address
+                 * space and soffset is the offset inside the pool bo
                  */
-                ib->gpu_addr = ib->sa_bo->soffset;
+                ib->gpu_addr = ib->sa_bo->soffset + RADEON_VA_IB_OFFSET;
         } else {
                 ib->gpu_addr = radeon_sa_bo_gpu_addr(ib->sa_bo);
         }