RE: [PATCH] hw/ppc: Improve build for PPC VFIO

[Duan, Zhenzhong]

>-----Original Message-----
>From: Cédric Le Goater <clg@redhat.com>
>Sent: Thursday, November 23, 2023 3:33 PM
>Subject: Re: [PATCH] hw/ppc: Improve build for PPC VFIO
>
>On 11/23/23 07:01, Zhenzhong Duan wrote:
>> VFIO is not a required subsystem for the pseries machine but it's
>> force enabled currently. When --without-default-devices is used
>> to drop some default devices including vfio-pci, vfio core code
>> is still kept which is unnecessary.
>>
>> Introduce a stub file to hold stub functions of VFIO EEH hooks,
>> then vfio core could be compiled out.
>>
>> Suggested-by: Cédric Le Goater <clg@redhat.com>
>> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
>
>
>Nick,
>
>I will take this patch through the vfio tree if that's OK for you.

Sure.

>
>> ---
>> Based on vfio-next/vfio-8.2
>>
>>   hw/ppc/spapr_pci_vfio_stub.c | 33 +++++++++++++++++++++++++++++++++
>>   hw/ppc/Kconfig               |  2 +-
>>   hw/ppc/meson.build           |  6 +++---
>>   3 files changed, 37 insertions(+), 4 deletions(-)
>>   create mode 100644 hw/ppc/spapr_pci_vfio_stub.c
>>
>> diff --git a/hw/ppc/spapr_pci_vfio_stub.c b/hw/ppc/spapr_pci_vfio_stub.c
>> new file mode 100644
>> index 0000000000..adb3fb5e35
>> --- /dev/null
>> +++ b/hw/ppc/spapr_pci_vfio_stub.c
>> @@ -0,0 +1,33 @@
>> +#include "qemu/osdep.h"
>> +#include "hw/pci-host/spapr.h"
>> +
>> +bool spapr_phb_eeh_available(SpaprPhbState *sphb)
>> +{
>> +    return false;
>> +}
>> +
>> +void spapr_phb_vfio_reset(DeviceState *qdev)
>> +{
>> +}
>> +
>> +int spapr_phb_vfio_eeh_set_option(SpaprPhbState *sphb,
>> +                                  unsigned int addr, int option)
>> +{
>> +    return RTAS_OUT_NOT_SUPPORTED;
>> +}
>> +
>> +int spapr_phb_vfio_eeh_get_state(SpaprPhbState *sphb, int *state)
>> +{
>> +    return RTAS_OUT_NOT_SUPPORTED;
>> +}
>> +
>> +int spapr_phb_vfio_eeh_reset(SpaprPhbState *sphb, int option)
>> +{
>> +    return RTAS_OUT_NOT_SUPPORTED;
>> +}
>> +
>> +int spapr_phb_vfio_eeh_configure(SpaprPhbState *sphb)
>> +{
>> +    return RTAS_OUT_NOT_SUPPORTED;
>> +}
>> +
>> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
>> index edc6d2d139..b8dabdbfbe 100644
>> --- a/hw/ppc/Kconfig
>> +++ b/hw/ppc/Kconfig
>> @@ -3,11 +3,11 @@ config PSERIES
>>       imply PCI_DEVICES
>>       imply TEST_DEVICES
>>       imply VIRTIO_VGA
>> +    imply VFIO if LINUX   # needed by spapr_pci_vfio.c
>
>Zhenzhong,
>
>I changed VFIO to VFIO_PCI because PPC only supports this type
>of passthrough devices.

Oh, I see, thanks

BRs.
Zhenzhong

>
>With that,
>
>Reviewed-by: Cédric Le Goater <clg@redhat.com>
>
>Thanks,
>
>C.
>
>
>
>>       select NVDIMM
>>       select DIMM
>>       select PCI
>>       select SPAPR_VSCSI
>> -    select VFIO_PCI if LINUX   # needed by spapr_pci_vfio.c
>>       select XICS
>>       select XIVE
>>       select MSI_NONBROKEN
>> diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
>> index ea44856d43..2df5db2eef 100644
>> --- a/hw/ppc/meson.build
>> +++ b/hw/ppc/meson.build
>> @@ -34,9 +34,9 @@ ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_TCG'],
>if_true: files(
>>     'spapr_softmmu.c',
>>   ))
>>   ppc_ss.add(when: 'CONFIG_SPAPR_RNG', if_true: files('spapr_rng.c'))
>> -ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_LINUX'], if_true: files(
>> -  'spapr_pci_vfio.c',
>> -))
>> +ppc_ss.add(when: [ 'CONFIG_VFIO_PCI', 'CONFIG_PSERIES', 'CONFIG_LINUX'],
>> +           if_true: files('spapr_pci_vfio.c'),
>> +           if_false: files('spapr_pci_vfio_stub.c'))
>>
>>   # IBM PowerNV
>>   ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(