[PATCH kernel v5 14/20] powerpc/powernv/npu: Add compound IOMMU groups

[Michael Ellerman]

Alexey Kardashevskiy <aik at ozlabs.ru> writes:
> diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
> index dc629ee..3468eaa 100644
> --- a/arch/powerpc/platforms/powernv/npu-dma.c
> +++ b/arch/powerpc/platforms/powernv/npu-dma.c
> @@ -372,8 +358,263 @@ struct npu {
...
> +
> +static void pnv_comp_attach_table_group(struct npu_comp *npucomp,
> +		struct pnv_ioda_pe *pe)
> +{
> +	if (WARN_ON(npucomp->pe_num == NV_NPU_MAX_PE_NUM))
> +		return;
> +
> +	npucomp->pe[npucomp->pe_num] = pe;
> +	++npucomp->pe_num;
> +}
> +
> +struct iommu_table_group *pnv_try_setup_npu_table_group(struct pnv_ioda_pe *pe)
> +{
> +	struct iommu_table_group *table_group;
> +	struct npu_comp *npucomp;
> +	struct pci_dev *gpdev = NULL;
> +	struct pci_controller *hose;
> +	struct pci_dev *npdev;
> +
> +	list_for_each_entry(gpdev, &pe->pbus->devices, bus_list) {
> +		npdev = pnv_pci_get_npu_dev(gpdev, 0);
> +		if (npdev)
> +			break;
> +	}
> +
> +	if (!npdev)
> +		/* It is not an NPU attached device, skip */
> +		return NULL;

This breaks some configs with:

  arch/powerpc/platforms/powernv/npu-dma.c:550:5: error: 'npdev' may be used uninitialized in this function [-Werror=uninitialized]

cheers