Re: [Qemu-devel] [PATCH v4 0/9] s390x: zPCI detangling

[Thomas Huth <thuth@redhat.com>]

On 08.08.2017 11:15, Cornelia Huck wrote:
> On Fri, 4 Aug 2017 16:59:34 +0200
> Cornelia Huck <cohuck@redhat.com> wrote:
> 
>> On Fri,  4 Aug 2017 13:29:37 +0200
>> Cornelia Huck <cohuck@redhat.com> wrote:
>>
>>> Next version, not so many changes from v3.
>>>
>>> As you might have guessed, the goals are still the same:
>>> - Being able to disable PCI support in a build completely.
>>> - Properly fencing off PCI if the relevant facility bit is not provided.
>>>
>>> Changes v3->v4:
>>> - introduce pci_available boolean
>>> - use pci_available to fence off setting the zcpi facility bit
>>> - collected tags
>>>
>>> Branch is still git://github.com/cohuck/qemu no-zpci-cpumodel  
>>
>> make check on a build with pci disabled revealed an interesting
>> inconsistency: We create a virtio-9p-ccw device, but the base
>> virtio-9p-device is in code that is not built for !pci.
>>
>> If I remove the pci dependency for hw/9pfs/ and fsdev/, things look
>> fine (at least on s390x). We probably need a different dependency,
>> though.
>>
>> virtio-9p maintainers, any suggestions?
> 
> I have the patch below, which is ugly, but seems to work for me. Better
> ideas welcome :)

I haven't tried whether it works, but you could maybe change the define
of CONFIG_VIRTFS instead:

diff --git a/configure b/configure
index dd73cce..64d21f6 100755
--- a/configure
+++ b/configure
@@ -5771,7 +5771,7 @@ if test "$libattr" = "yes" ; then
   echo "CONFIG_LIBATTR=y" >> $config_host_mak
 fi
 if test "$virtfs" = "yes" ; then
-  echo "CONFIG_VIRTFS=y" >> $config_host_mak
+  echo 'CONFIG_VIRTFS=$(call lor, $(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW)' >> $config_host_mak
 fi
 if test "$vhost_scsi" = "yes" ; then
   echo "CONFIG_VHOST_SCSI=y" >> $config_host_mak

... I think that should simplify the other statements quite a bit since
you then only have to test CONFIG_VIRTFS in the other locations?

 Thomas


> From 0ba6427e7ac7cef38b487d28c9dce653d8cb9a71 Mon Sep 17 00:00:00 2001
> From: Cornelia Huck <cohuck@redhat.com>
> Date: Tue, 8 Aug 2017 11:03:38 +0200
> Subject: [PATCH] 9pfs: fix dependencies
> 
> Nothing in fsdev/ or hw/9pfs/ depends on pci; it should rather depend
> on CONFIG_VIRTFS and on the presence of an appropriate virtio transport
> device.
> 
> Let's introduce CONFIG_VIRTIO_CCW to cover s390x and check for
> CONFIG_VIRTFS && (CONFIG_VIRTIO_PCI || CONFIG_VIRTIO_CCW).
> 
> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
> ---
>  default-configs/s390x-softmmu.mak | 1 +
>  fsdev/Makefile.objs               | 9 +++------
>  hw/Makefile.objs                  | 2 +-
>  3 files changed, 5 insertions(+), 7 deletions(-)
> 
> diff --git a/default-configs/s390x-softmmu.mak b/default-configs/s390x-softmmu.mak
> index 6ab2bc65ac..7f15ab68b1 100644
> --- a/default-configs/s390x-softmmu.mak
> +++ b/default-configs/s390x-softmmu.mak
> @@ -8,3 +8,4 @@ CONFIG_S390_FLIC=y
>  CONFIG_S390_FLIC_KVM=$(CONFIG_KVM)
>  CONFIG_VFIO_CCW=$(CONFIG_LINUX)
>  CONFIG_WDT_DIAG288=y
> +CONFIG_VIRTIO_CCW=y
> diff --git a/fsdev/Makefile.objs b/fsdev/Makefile.objs
> index 659df6e187..10d8caa291 100644
> --- a/fsdev/Makefile.objs
> +++ b/fsdev/Makefile.objs
> @@ -1,10 +1,7 @@
> -ifeq ($(CONFIG_VIRTIO)$(CONFIG_VIRTFS)$(CONFIG_PCI),yyy)
>  # Lots of the fsdev/9pcode is pulled in by vl.c via qemu_fsdev_add.
> -# only pull in the actual virtio-9p device if we also enabled virtio.
> -common-obj-y = qemu-fsdev.o 9p-marshal.o 9p-iov-marshal.o
> -else
> -common-obj-y = qemu-fsdev-dummy.o
> -endif
> +# only pull in the actual virtio-9p device if we also enabled a virtio backend.
> +common-obj-$(call land, $(CONFIG_VIRTFS),$(call lor, $(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW)))= qemu-fsdev.o 9p-marshal.o 9p-iov-marshal.o
> +common-obj-$(call lnot, $(call land, $(CONFIG_VIRTFS),$(call lor, $(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW)))) = qemu-fsdev-dummy.o
>  common-obj-y += qemu-fsdev-opts.o qemu-fsdev-throttle.o
>  
>  # Toplevel always builds this; targets without virtio will put it in
> diff --git a/hw/Makefile.objs b/hw/Makefile.objs
> index a2c61f6b09..10942fe0b4 100644
> --- a/hw/Makefile.objs
> +++ b/hw/Makefile.objs
> @@ -1,4 +1,4 @@
> -devices-dirs-$(call land, $(CONFIG_VIRTIO),$(call land,$(CONFIG_VIRTFS),$(CONFIG_PCI))) += 9pfs/
> +devices-dirs-$(call land, $(CONFIG_VIRTFS),$(call lor,$(CONFIG_VIRTIO_PCI),$(CONFIG_VIRTIO_CCW))) += 9pfs/
>  devices-dirs-$(CONFIG_SOFTMMU) += acpi/
>  devices-dirs-$(CONFIG_SOFTMMU) += adc/
>  devices-dirs-$(CONFIG_SOFTMMU) += audio/
>