On Thu, 18 Feb 2021 10:23:16 +0100 Thomas Huth <th...@redhat.com> wrote:
> > Since the virtio-gpu-ccw device depends on the hw-display-virtio-gpu > > module, which provides the type virtio-gpu-device, packaging the > > hw-display-virtio-gpu module as a separate package that may or may not > > be installed along with the qemu package leads to problems. Namely if > > the hw-display-virtio-gpu is absent, qemu continues to advertise > > virtio-gpu-ccw, but it aborts not only when one attempts using > > virtio-gpu-ccw, but also when libvirtd's capability probing tries > > to instantiate the type to introspect it. > > > > Let us thus introduce a module named hw-s390x-virtio-gpu-ccw that > > is going to provide the virtio-gpu-ccw device. The hw-s390x prefix > > was chosen because it is not a portable device. > > > > With virtio-gpu-ccw built as a module, the correct way to package a > > modularized qemu is to require that hw-display-virtio-gpu must be > > installed whenever the module hw-s390x-virtio-gpu-ccw. > > > > Signed-off-by: Halil Pasic <pa...@linux.ibm.com> > > --- > > hw/s390x/meson.build | 17 ++++++++++++++++- > > util/module.c | 1 + > > 2 files changed, 17 insertions(+), 1 deletion(-) > > > > diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build > > index 2a7818d94b..153b1309fb 100644 > > --- a/hw/s390x/meson.build > > +++ b/hw/s390x/meson.build > > @@ -34,7 +34,6 @@ virtio_ss.add(files('virtio-ccw.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_BALLOON', if_true: > > files('virtio-ccw-balloon.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_BLK', if_true: > > files('virtio-ccw-blk.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true: > > files('virtio-ccw-crypto.c')) > > -virtio_ss.add(when: 'CONFIG_VIRTIO_GPU', if_true: > > files('virtio-ccw-gpu.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_INPUT', if_true: > > files('virtio-ccw-input.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_NET', if_true: > > files('virtio-ccw-net.c')) > > virtio_ss.add(when: 'CONFIG_VIRTIO_RNG', if_true: > > files('virtio-ccw-rng.c')) > > @@ -46,3 +45,19 @@ virtio_ss.add(when: 'CONFIG_VHOST_USER_FS', if_true: > > files('vhost-user-fs-ccw.c' > > s390x_ss.add_all(when: 'CONFIG_VIRTIO_CCW', if_true: virtio_ss) > > > > hw_arch += {'s390x': s390x_ss} > > + > > +if target.startswith('s390x') > > + hw_s390x_modules = {} > > + > > + hw_s390x_modules_c_args = ['-DNEED_CPU_H', > > + '-DCONFIG_TARGET="@0@-config-target.h"'.format(target)] > > + hw_s390x_modules_inc = [include_directories('../../target' / > > config_target['TARGET_BASE_ARCH'])] > > + hw_s390x_modules_dependencies = declare_dependency( > > + include_directories: hw_s390x_modules_inc, compile_args: > > hw_s390x_modules_c_args) > > Basically the patch looks fine to me, but I wonder why all that above lines > (related to hw_s390x_modules_dependencies) are requred at all? The other > display modules in hw/display/meson.build also do not need to re-define > c_args for example? The explanation is simple. Unlike most devices, the ccw devices aren't portable. In particular both css.c and css.h includes "cpu.h", and virtio-ccw-gpu.c includes "qemu/osdep.h". Furthermore osdep.h contains: #ifdef NEED_CPU_H #include CONFIG_TARGET #else #include "exec/poison.h" #endif so if we don't have NEED_CPU_H, among others CONFIG_KVM is poisoned, and CONFIG_KVM is used in "css.h". Frankly, I can't tell under what circumstances does css need "cpu.h". I managed to build the s390x-softmmu target without it, but decided to put it back. Regarding "osdep.h", I just assumed includes are done the way they are done for a good reason. Maybe the includes can be changed in a way that the things you ask about become unnecessary, but with the code as is they are necessary. Try to drop them and check out what happens. Regards, Halil