Re: [PATCH] hw/s390x/s390-pci-inst.c: Use device_cold_reset() to reset PCI devices

[Matthew Rosato <mjrosato@linux.ibm.com>]

On 10/13/22 1:21 PM, Peter Maydell wrote:
> The semantic difference between the deprecated device_legacy_reset()
> function and the newer device_cold_reset() function is that the new
> function resets both the device itself and any qbuses it owns,
> whereas the legacy function resets just the device itself and nothing
> else.
> 
> In s390-pci-inst.c we use device_legacy_reset() to reset an
> S390PCIBusDevice.  This device doesn't have any child qbuses, so the
> functions do the same thing and we can stop using the deprecated one.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> NB: tested only with 'make check' and 'make check-avocado', which
> probably don't exercise this codepath.
>

I exercised the codepath by triggering the associated clp using both virtio and vfio pci devices on s390x; looks good to me.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>

 
>  hw/s390x/s390-pci-inst.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
> index 20a9bcc7afb..16f5a3e81b4 100644
> --- a/hw/s390x/s390-pci-inst.c
> +++ b/hw/s390x/s390-pci-inst.c
> @@ -272,7 +272,7 @@ int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra)
>                  stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_FHOP);
>                  goto out;
>              }
> -            device_legacy_reset(DEVICE(pbdev));
> +            device_cold_reset(DEVICE(pbdev));
>              pbdev->fh &= ~FH_MASK_ENABLE;
>              pbdev->state = ZPCI_FS_DISABLED;
>              stl_p(&ressetpci->fh, pbdev->fh);