Re: [PATCH v3 1/8] pc-bios/s390-ccw: Check if a PCI function is already enabled before trying to enable it

["Jason J. Herne" <jjherne@linux.ibm.com>]

On 8/31/26 3:49 PM, jrossi@linux.ibm.com wrote:
> From: Jared Rossi <jrossi@linux.ibm.com>
> 
> Enabling a PCI function that is already configured will result in an error.
> Simply check if the device has already been enabled, and if so, return
> without doing anything further; otherwise, enable it as usual.
> 
> Also, because enable_pci_function() prints its own message, let's remove
> the duplicate message emitted during the virtio PCI setup steps.
> 
> Reviewed-by: Zhuoying Cai <zycai@linux.ibm.com>
> Reviewed-by: Eric Farman <farman@linux.ibm.com>
> Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
> ---
>   pc-bios/s390-ccw/clp.c        | 4 ++++
>   pc-bios/s390-ccw/virtio-pci.c | 1 -
>   2 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/pc-bios/s390-ccw/clp.c b/pc-bios/s390-ccw/clp.c
> index ca9565d8de..7917f13345 100644
> --- a/pc-bios/s390-ccw/clp.c
> +++ b/pc-bios/s390-ccw/clp.c
> @@ -82,6 +82,10 @@ int enable_pci_function(uint32_t *fhandle)
>   {
>       ClpReqRspSetPci rrb;
>   
> +    if (*fhandle & CLP_FHLIST_MASK_CONFIG) {
> +        return 0;   /* already enabled */
> +    }
> +
>       rrb.request.hdr.len = sizeof(ClpReqSetPci);
>       rrb.request.hdr.cmd = 0x05;
>       rrb.request.fh = *fhandle;
> diff --git a/pc-bios/s390-ccw/virtio-pci.c b/pc-bios/s390-ccw/virtio-pci.c
> index f501252c81..231ab6e04d 100644
> --- a/pc-bios/s390-ccw/virtio-pci.c
> +++ b/pc-bios/s390-ccw/virtio-pci.c
> @@ -452,7 +452,6 @@ int virtio_pci_setup_device(void)
>       VDev *vdev = virtio_get_device();
>   
>       if (enable_pci_function(&vdev->pci_fh)) {
> -        puts("Failed to enable PCI function");
>           return -ENODEV;
>       }
>   

Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>