Re: [Qemu-devel] [RFC PATCH v4 00/44] Support Kconfig in QEMU

[Paolo Bonzini]

On 24/01/19 03:00, Yang Zhong wrote:
> On Thu, Jan 24, 2019 at 02:09:25AM +0100, Paolo Bonzini wrote:
>> On 23/01/19 07:55, Yang Zhong wrote:
>>> This Kconfig implementation is rebased from Paolo's branch
>>> https://github.com/bonzini/qemu/commits/kconfig
>>>
>>> I rebased most of patches except non-x86 ARCHs dependency definitions
>>> this time.
>>> https://github.com/yangzhon/qemu/commits/topic/upstream/Kconfig
>>>
>>> The current RFC patches only support
>>> (*) x86_64 platform build
>>>     Once design is fixed, we can do other archs.
>>>
>>> (*) defconfig
>>>     "randconfig" build has some issues, which are mostly related
>>>     with CONFIG* in Kconfig.host abd configure. In randconfig mode,
>>>     some CONFIG* has different setting value in config-host.mak and
>>>     %/config-device.mak, which make QEMU build failure.
>>>
>>> (*) Kconfig in hw/ directory
>>>
>>> The current configure and build command are same with previous
>>> commands and if we want to disable or enable some features, like
>>> "tcg", we still need add "--enable/--disable-tcg" in configure
>>> command line. If we want to disable one emulation device, we can
>>> disable this in related Kconfig file in hw/ directory.
>>>
>>> The current build command:
>>> (*) ./configure --target-list=x86_64-softmmu
>>> (*) make -j8
>>>
>>> Since the Kconfig language replace traditional CONFIG_* in
>>> default-config/%-softmmu.mak, the %-softmmu.mak file only
>>> define embeded boards or machines, like 440fx and Q35 in x86_64
>>> platform. The Kconfig has already defined dependency topology
>>> between different Kconfig files, but there are still some issues
>>>
>>> (*) Kconfig for configure(config-host.mak)
>>>     Some CONFIG* in configure  need some logic to generate, those
>>>     are hard to input this CONFIG* in Kconfig.host or Kconfig* file.
>>>
>>> (*) Kconfig for %config-target.mak
>>>     The CONFIG* in %/config-target.mak file, this is still related
>>>     with configure.
>>>
>>> (*) randconfig support issue.
>>>
>>> Before this RFC patches, we have talked Kconfig in another thread
>>> http://lists.nongnu.org/archive/html/qemu-devel/2018-09/msg02827.html
>>>
>>> Please give your comments on this RFC thread, many thanks!
>>
>> I started looking at this, and found two bugs in current code
>> (unreachable devices that shouldn't be there - SERIAL_ISA for ARM,
>> ACPI_NVDIMM for MIPS).  There are a few issues in that the script is not
>> Python 3-enabled and only x86 compiles, but they are easily fixed.  A
>> slightly bigger thing is to make VFIO configuration more fine-grained
>> and express it with kconfig dependencies, but it's just a couple patches
>> in the same spirit as these ones.  I'll look at randconfig next.
>>
>   Yes, thanks Paolo. The v4 patches have gotten new comments from other
>   maintainers, and i will send v5 patches in next week. 

Ok, I'll pass you offlist a tree to use as a base for v5.

Paolo