Re: [PATCH v2] ACPI: PCI: Release excess memory usage.

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Tue, 29 Apr 2025 17:10:51 +0800
Zhe Qiao <qiaozhe@iscas.ac.cn> wrote:

> In the pci_acpi_scan_root() function, if the PCI bus creation failed,
> the allocated memory should be released to avoid memory occupation.
> 
> Fixes: 789befdfa389 ("arm64: PCI: Migrate ACPI related functions to pci-acpi.c")
> Signed-off-by: Zhe Qiao <qiaozhe@iscas.ac.cn>
> 
> ---
> V1 -> V2:
> Modified labels for better readability.
> 
> ---
>  drivers/pci/pci-acpi.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
> index af370628e583..bde104ecac80 100644
> --- a/drivers/pci/pci-acpi.c
> +++ b/drivers/pci/pci-acpi.c
> @@ -1677,15 +1677,12 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>  
>  	root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL);
>  	if (!root_ops) {
> -		kfree(ri);
> -		return NULL;
> +		goto free_ri;
>  	}
>  
>  	ri->cfg = pci_acpi_setup_ecam_mapping(root);
>  	if (!ri->cfg) {
> -		kfree(ri);
> -		kfree(root_ops);
> -		return NULL;
> +		goto free_root_ops;
>  	}
>  
>  	root_ops->release_info = pci_acpi_generic_release_info;
> @@ -1693,7 +1690,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>  	root_ops->pci_ops = (struct pci_ops *)&ri->cfg->ops->pci_ops;
>  	bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg);
>  	if (!bus)
> -		return NULL;

Do we also need to tear down the ecam mapping done in pci_acpi_setup_ecam_mapping()?
Might just be pci_ecam_free(ri->cfg);


> +		goto free_root_ops;
>  
>  	/* If we must preserve the resource configuration, claim now */
>  	host = pci_find_host_bridge(bus);
> @@ -1710,6 +1707,12 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>  		pcie_bus_configure_settings(child);
>  
>  	return bus;
> +
> +free_root_ops:
> +	kfree(root_ops);
> +free_ri:
> +	kfree(ri);
> +	return NULL;
>  }
>  
>  void pcibios_add_bus(struct pci_bus *bus)