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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: c67cb19811ec ("drm/amdgpu: Implement UALink handle export") > Assisted-by: LLM > Signed-off-by: Karl Mehltretter Thanks for the catch. I'm applying the patch to amd-staging-drm-next. Reviewed-by: Felix Kuehling Mukul is looking into the other pre-existing issues pointed out by Sashiko. Regards,   Felix > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c > index ab56420..c6b7122 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ualink.c > @@ -1819,7 +1819,7 @@ static void amdgpu_ualink_npa_mm_fini(struct amdgpu_device *adev) > static void amdgpu_generate_ualink_handle(struct amdgpu_device *adev, > struct amdgpu_ualink_handle *handle) > { > - bool unique; > + bool unique = false; > > do { > handle->handle_lo = get_random_u64(); > base-commit: 68142f986ff04b2b70b31db00f719bf690f64a9a