Re: [PULL 5/5] m68k: add Virtual M68k Machine

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 3/18/21 10:52 AM, Laurent Vivier wrote:
> Le 18/03/2021 à 10:19, Philippe Mathieu-Daudé a écrit :
>> Hi Laurent,
>>
>> +Paolo / Thomas
>>
>> On 3/15/21 9:42 PM, Laurent Vivier wrote:
>>> The machine is based on Goldfish interfaces defined by Google
>>> for Android simulator. It uses Goldfish-rtc (timer and RTC),
>>> Goldfish-pic (PIC) and Goldfish-tty (for serial port and early tty).
>>>
>>> The machine is created with 128 virtio-mmio bus, and they can
>>> be used to use serial console, GPU, disk, NIC, HID, ...
>>>
>>> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
>>> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
>>> Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>>> Message-Id: <20210312214145.2936082-6-laurent@vivier.eu>
>>> ---
>>>  default-configs/devices/m68k-softmmu.mak      |   1 +
>>>  .../standard-headers/asm-m68k/bootinfo-virt.h |  18 +
>>>  hw/m68k/virt.c                                | 313 ++++++++++++++++++
>>>  MAINTAINERS                                   |  13 +
>>>  hw/m68k/Kconfig                               |   9 +
>>>  hw/m68k/meson.build                           |   1 +
>>>  6 files changed, 355 insertions(+)
>>>  create mode 100644 include/standard-headers/asm-m68k/bootinfo-virt.h
>>>  create mode 100644 hw/m68k/virt.c
>>
>>> diff --git a/hw/m68k/Kconfig b/hw/m68k/Kconfig
>>> index 60d7bcfb8f2b..f839f8a03064 100644
>>> --- a/hw/m68k/Kconfig
>>> +++ b/hw/m68k/Kconfig
>>> @@ -23,3 +23,12 @@ config Q800
>>>      select ESP
>>>      select DP8393X
>>>      select OR_IRQ
>>> +
>>> +config M68K_VIRT
>>> +    bool
>>> +    select M68K_IRQC
>>> +    select VIRT_CTRL
>>> +    select GOLDFISH_PIC
>>> +    select GOLDFISH_TTY
>>> +    select GOLDFISH_RTC
>>> +    select VIRTIO_MMIO
>>
>> I had this error on gitlab:
>>
>> (qemu) QEMU_PROG: -drive driver=IMGFMT,file=TEST_DIR/t.IMGFMT,if=virtio:
>> 'virtio-blk-pci' is not a valid device model name
>> job: check-system-fedora
>> https://gitlab.com/philmd/qemu/-/jobs/1106469724
>>
>> I bisected locally to this commit.
>>
>> check-system-fedora uses build-system-fedora:
>>
>> build-system-fedora:
>>     CONFIGURE_ARGS: --disable-gcrypt --enable-nettle --enable-docs
>>              --enable-fdt=system --enable-slirp=system
>>              --enable-capstone=system
>>
>> I'm confused because the machine provides a VIRTIO bus
>> via MMIO:
>>
>> config VIRTIO_MMIO
>>     bool
>>     select VIRTIO
>>
>> I remember I tested your machine with virtio-blk-device.
>>
>> config VIRTIO_BLK
>>     bool
>>     default y
>>     depends on VIRTIO
>>
>> Ah, this is virtio-blk-pci, which has:
>>
>> virtio_pci_ss.add(when: 'CONFIG_VIRTIO_BLK', if_true:
>> files('virtio-blk-pci.c'))
>> virtio_ss.add_all(when: 'CONFIG_VIRTIO_PCI', if_true: virtio_pci_ss)
>>
>> And VIRTIO_PCI isn't selected...
> 
> This machine doesn't have virtio-pci, but only virtio-mmio buses.

Yes. I meant "VIRTIO_PCI isn't selected, which is the correct config
for this machine". So the problem isn't the m68k-virt machine addition,
but it shows another problem elsewhere.

>> Are the tests incorrect then?
>>
>> libqos isn't restricted to PCI:
>>
>> tests/qtest/libqos/virtio-blk.c:24:#include "virtio-blk.h"
>> tests/qtest/libqos/virtio-blk.c:29:/* virtio-blk-device */
>> tests/qtest/libqos/virtio-blk.c:33:    if (!g_strcmp0(interface,
>> "virtio-blk")) {
>> tests/qtest/libqos/virtio-blk.c:40:    fprintf(stderr, "%s not present
>> in virtio-blk-device\n", interface);
>> tests/qtest/libqos/virtio-blk.c:109:    /* virtio-blk-device */
>> tests/qtest/libqos/virtio-blk.c:111:
>> qos_node_create_driver("virtio-blk-device", virtio_blk_device_create);
>> tests/qtest/libqos/virtio-blk.c:112:
>> qos_node_consumes("virtio-blk-device", "virtio-bus", &opts);
>> tests/qtest/libqos/virtio-blk.c:113:
>> qos_node_produces("virtio-blk-device", "virtio-blk");
>>
>> But qemu-iotests / qtests do use virtio-blk-pci. Maybe they should
>> use a generic virtio-blk-device instead, hoping it get plugged correctly
>> to the virtio bus...
> 
> Yes, it's how the machine work: it has 128 virtio-mmio buses and virtio-devices are plugged directly
> in the first free ones.
> 
> I think the fix would be to disable the virtio-blk-pci test for the machines without PCI bus.
> 
> Why is it executed for now?

This is probably the problem root cause.

Possible fix:

-->8 --
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index 66ee9fbf450..d7f3fad51c1 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -217,13 +217,17 @@
   'emc141x-test.c',
   'usb-hcd-ohci-test.c',
   'virtio-test.c',
-  'virtio-blk-test.c',
-  'virtio-net-test.c',
-  'virtio-rng-test.c',
-  'virtio-scsi-test.c',
   'virtio-serial-test.c',
   'vmxnet3-test.c',
 )
+if config_all_devices.has_key('CONFIG_VIRTIO_PCI')
+  qos_test_ss.add(
+    'virtio-blk-test.c',
+    'virtio-net-test.c',
+    'virtio-rng-test.c',
+    'virtio-scsi-test.c',
+  )
+endif
 if have_virtfs
   qos_test_ss.add(files('virtio-9p-test.c'))
 endif
---

I'll test that locally but not on Gitlab.

Thanks,

Phil.