drm/amdgpu: Fix size validation for non-exclusive domains (v4)

[ Upstream commit 7554886daa31eacc8e7fac9e15bbce67d10b8f1f ]

Fix amdgpu_bo_validate_size() to check whether the TTM domain manager for the
requested memory exists, else we get a kernel oops when dereferencing "man".

v2: Make the patch standalone, i.e. not dependent on local patches.
v3: Preserve old behaviour and just check that the manager pointer is not
    NULL.
v4: Complain if GTT domain requested and it is uninitialized--most likely a
    bug.

Cc: Alex Deucher <Alexander.Deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: AMD Graphics <amd-gfx@lists.freedesktop.org>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index 3df13d8..3be3cba 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -446,27 +446,24 @@ static bool amdgpu_bo_validate_size(struct amdgpu_device *adev,
 
        /*
         * If GTT is part of requested domains the check must succeed to
-        * allow fall back to GTT
+        * allow fall back to GTT.
         */
        if (domain & AMDGPU_GEM_DOMAIN_GTT) {
                man = ttm_manager_type(&adev->mman.bdev, TTM_PL_TT);
 
-               if (size < man->size)
+               if (man && size < man->size)
                        return true;
-               else
-                       goto fail;
-       }
-
-       if (domain & AMDGPU_GEM_DOMAIN_VRAM) {
+               else if (!man)
+                       WARN_ON_ONCE("GTT domain requested but GTT mem manager uninitialized");
+               goto fail;
+       } else if (domain & AMDGPU_GEM_DOMAIN_VRAM) {
                man = ttm_manager_type(&adev->mman.bdev, TTM_PL_VRAM);
 
-               if (size < man->size)
+               if (man && size < man->size)
                        return true;
-               else
-                       goto fail;
+               goto fail;
        }
 
-
        /* TODO add more domains checks, such as AMDGPU_GEM_DOMAIN_CPU */
        return true;