On 12/03/2026 14:13, Srinivasan Shanmugam wrote:
amdgpu_vm_bo_update() allows bo_va->base.bo to be NULL in some paths,
such as PRT-only updates.
Although amdgpu_vm_is_bo_always_valid() already returns false for a NULL
BO, Smatch still warns that bo may be NULL before it is dereferenced
later in the block.
Add an explicit `bo &&` check before calling
amdgpu_vm_is_bo_always_valid() to make the non-NULL condition clear and
fixes the below smatch error
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1353 amdgpu_vm_bo_update() error: we
previously assumed 'bo' could be null (see line 1292)
Fixes: 26e20235ce00 ("drm/amdgpu: Add amdgpu_bo_is_vm_bo helper")
Cc: Dan Carpenter <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Signed-off-by: Srinivasan Shanmugam <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index b89013a6aa0b..0d26346178d4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1349,7 +1349,7 @@ int amdgpu_vm_bo_update(struct amdgpu_device *adev,
struct amdgpu_bo_va *bo_va,
* the evicted list so that it gets validated again on the
* next command submission.
*/
- if (amdgpu_vm_is_bo_always_valid(vm, bo)) {
+ if (bo && amdgpu_vm_is_bo_always_valid(vm, bo)) {
That would be unfortunate:
bool amdgpu_vm_is_bo_always_valid(struct amdgpu_vm *vm, struct amdgpu_bo
*bo)
{
return bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv;
}
Maybe Dan can make smatch smarter? :) Because I don't think papering
randomly at a single call site is great. It is even in the same
compilation unit. Hmm does the order matter to smatch? Should we maybe
move amdgpu_vm_is_bo_always_valid() to be earlier in the file?
Regards,
Tvrtko
if (bo->tbo.resource &&
!(bo->preferred_domains &
amdgpu_mem_type_to_domain(bo->tbo.resource->mem_type)))
