Re: [PATCH] vfio/pci: Fix handling of pci use accessor return codes

[Cornelia Huck <cohuck@redhat.com>]

On Sun, 24 Jan 2021 16:35:41 +0100
Heiner Kallweit <hkallweit1@gmail.com> wrote:

> The pci user accessors return negative errno's on error.
> 
> Fixes: f572a960a15e ("vfio/pci: Intel IGD host and LCP bridge config space access")
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/vfio/pci/vfio_pci_igd.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/vfio/pci/vfio_pci_igd.c b/drivers/vfio/pci/vfio_pci_igd.c
> index 53d97f459..e66dfb017 100644
> --- a/drivers/vfio/pci/vfio_pci_igd.c
> +++ b/drivers/vfio/pci/vfio_pci_igd.c
> @@ -127,7 +127,7 @@ static size_t vfio_pci_igd_cfg_rw(struct vfio_pci_device *vdev,
>  
>  		ret = pci_user_read_config_byte(pdev, pos, &val);
>  		if (ret)
> -			return pcibios_err_to_errno(ret);
> +			return ret;

This is actually not strictly needed, as pcibios_err_to_errno() already
keeps errors <= 0 unchanged, so more a cleanup than a fix?

Anyway,

Reviewed-by: Cornelia Huck <cohuck@redhat.com>

>  
>  		if (copy_to_user(buf + count - size, &val, 1))
>  			return -EFAULT;