Re: [PATCH 2/3] powerpc/pci: Fix pcibios_setup_device() ordering

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 30/09/2019 12:08, Oliver O'Halloran wrote:
> From: Shawn Anastasio <shawn@anastas.io>
> 
> Move PCI device setup from pcibios_add_device() and pcibios_fixup_bus() to
> pcibios_bus_add_device(). This ensures that platform-specific DMA and IOMMU
> setup occurs after the device has been registered in sysfs, which is a
> requirement for IOMMU group assignment to work
> 
> This fixes IOMMU group assignment for hotplugged devices on pseries, where
> the existing behavior results in IOMMU assignment before registration.
> 
> Thanks to Lukas Wunner <lukas@wunner.de> for the suggestion.
> 
> Signed-off-by: Shawn Anastasio <shawn@anastas.io>



Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>

> ---
>  arch/powerpc/kernel/pci-common.c | 25 +++++++++----------------
>  1 file changed, 9 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
> index 1c448cf..b89925ed 100644
> --- a/arch/powerpc/kernel/pci-common.c
> +++ b/arch/powerpc/kernel/pci-common.c
> @@ -261,12 +261,6 @@ int pcibios_sriov_disable(struct pci_dev *pdev)
>  
>  #endif /* CONFIG_PCI_IOV */
>  
> -void pcibios_bus_add_device(struct pci_dev *pdev)
> -{
> -	if (ppc_md.pcibios_bus_add_device)
> -		ppc_md.pcibios_bus_add_device(pdev);
> -}
> -
>  static resource_size_t pcibios_io_size(const struct pci_controller *hose)
>  {
>  #ifdef CONFIG_PPC64
> @@ -987,15 +981,17 @@ static void pcibios_setup_device(struct pci_dev *dev)
>  		ppc_md.pci_irq_fixup(dev);
>  }
>  
> -int pcibios_add_device(struct pci_dev *dev)
> +void pcibios_bus_add_device(struct pci_dev *pdev)
>  {
> -	/*
> -	 * We can only call pcibios_setup_device() after bus setup is complete,
> -	 * since some of the platform specific DMA setup code depends on it.
> -	 */
> -	if (dev->bus->is_added)
> -		pcibios_setup_device(dev);
> +	/* Perform platform-specific device setup */
> +	pcibios_setup_device(pdev);
> +
> +	if (ppc_md.pcibios_bus_add_device)
> +		ppc_md.pcibios_bus_add_device(pdev);
> +}
>  
> +int pcibios_add_device(struct pci_dev *dev)
> +{
>  #ifdef CONFIG_PCI_IOV
>  	if (ppc_md.pcibios_fixup_sriov)
>  		ppc_md.pcibios_fixup_sriov(dev);
> @@ -1037,9 +1033,6 @@ void pcibios_fixup_bus(struct pci_bus *bus)
>  
>  	/* Now fixup the bus bus */
>  	pcibios_setup_bus_self(bus);
> -
> -	/* Now fixup devices on that bus */
> -	pcibios_setup_bus_devices(bus);
>  }
>  EXPORT_SYMBOL(pcibios_fixup_bus);
>  
> 

-- 
Alexey