drm/amdgpu: Initialize UALink handle uniqueness state

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amdgpu_generate_ualink_handle() continues when handle_lo is zero. For
accelerator ID 0, the random value can become zero after the low 10 bits
are cleared. This path reaches while (!unique) without assigning unique.

Clang's -Wconditional-uninitialized reports the read. A reduced
MemorySanitizer test reports use-of-uninitialized-value at the loop
condition.

If the uninitialized value ends the loop, handle 0 is inserted into
exp_xa while robj->ualink_handle_lo still says that the BO has no handle.
A later export can create another entry for the same BO.

Initialize unique to false so the zero-handle path repeats the loop.

Fixes: c67cb19811 ("drm/amdgpu: Implement UALink handle export")
Assisted-by: LLM
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Signed-off-by: Felix Kuehling <felix.kuehling@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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Karl Mehltretter 2026-09-14 07:46:04 +02:00 • committed by Alex Deucher

parent 13d44ca033

commit c73391c589

1 changed files with 1 additions and 1 deletions

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drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c

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