[PATCH AUTOSEL 6.1 5/7] drm/amdgpu: Fix size validation for non-exclusive domains (v4)

From: Sasha Levin
Date: Sat Dec 31 2022 - 15:05:15 EST


From: Luben Tuikov <luben.tuikov@xxxxxxx>

[ 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@xxxxxxx>
Cc: Christian König <christian.koenig@xxxxxxx>
Cc: AMD Graphics <amd-gfx@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Luben Tuikov <luben.tuikov@xxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index 2e8f6cd7a729..33e266433e9b 100644
--- 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;

--
2.35.1