Re: [PATCH RESEND v5 05/18] PCI: dwc: Deallocate EPC memory on EP init error

[Manivannan Sadhasivam]

On Fri, Jun 24, 2022 at 05:34:15PM +0300, Serge Semin wrote:
> If the dw_pcie_ep_init() method fails to perform any action after the EPC
> memory is initialized and the MSI memory region is allocated, the later
> parts won't be undone thus causing the memory leak.  Let's fix that by
> introducing the cleanup-on-error path in the dw_pcie_ep_init() method,
> which will be taken should any consequent erroneous situation happens.
> 
> Fixes: 2fd0c9d966cc ("PCI: designware-ep: Pre-allocate memory for MSI in dw_pcie_ep_init")
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

Thanks,
Mani

> Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> 
> ---
> 
> Changelog v2:
> - This is a new patch create as a result of the discussion in:
>   Link: https://lore.kernel.org/linux-pci/20220324014836.19149-26-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx
> ---
>  .../pci/controller/dwc/pcie-designware-ep.c    | 18 ++++++++++++++++--
>  1 file changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 0eda8236c125..13c2e73f0eaf 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -780,8 +780,9 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
>  	ep->msi_mem = pci_epc_mem_alloc_addr(epc, &ep->msi_mem_phys,
>  					     epc->mem->window.page_size);
>  	if (!ep->msi_mem) {
> +		ret = -ENOMEM;
>  		dev_err(dev, "Failed to reserve memory for MSI/MSI-X\n");
> -		return -ENOMEM;
> +		goto err_exit_epc_mem;
>  	}
>  
>  	if (ep->ops->get_features) {
> @@ -790,6 +791,19 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
>  			return 0;
>  	}
>  
> -	return dw_pcie_ep_init_complete(ep);
> +	ret = dw_pcie_ep_init_complete(ep);
> +	if (ret)
> +		goto err_free_epc_mem;
> +
> +	return 0;
> +
> +err_free_epc_mem:
> +	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
> +			      epc->mem->window.page_size);
> +
> +err_exit_epc_mem:
> +	pci_epc_mem_exit(epc);
> +
> +	return ret;
>  }
>  EXPORT_SYMBOL_GPL(dw_pcie_ep_init);
> -- 
> 2.35.1
> 

-- 
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