Re: s390x/qemu-user: TODO /home/dhildenb/git/qemu/tcg/tci.c:859: tcg_qemu_tb_exec()

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

On 10/17/19 12:35 PM, David Hildenbrand wrote:
> On 17.10.19 12:25, Philippe Mathieu-Daudé wrote:
>> Hi David,
>>
>> On 10/17/19 12:02 PM, David Hildenbrand wrote:
>>> Hi,
>>>
>>> I'm currently trying to run Fedora 31 under qemu-user
>>> (https://github.com/fedora-cloud/docker-brew-fedora/tree/8a81f67271e959dfc8f8a888b161bbd540b7a83b/s390x) 
>>>
>>> in order to debug  a vector instruction issue.
>>>
>>> Strangely, when trying to chroot into above rootfs and running
>>> /bin/bash, I get
>>>
>>> t460s: ~/f31  $ sudo chroot . ./qemu-s390x  /bin/bash
>>> TODO /home/dhildenb/git/qemu/tcg/tci.c:859: tcg_qemu_tb_exec()
>>> /home/dhildenb/git/qemu/tcg/tci.c:859: tcg fatal error
>>> Aborted
>>>
>>>
>>> But it's not fundamentally broken:
>>>
>>> t460s: ~/f31  $ sudo chroot . ./qemu-s390x  /bin/ls
>>> bin   dev  home  lib64       media  opt   qemu-s390x  run   srv  tmp  
>>> var
>>> boot  etc  lib   lost+found  mnt    proc  root        sbin  sys  usr
>>>
>>>
>>> I do wonder why we don't run into the same issue under qemu-systems390x.
>>
>> Are you also using TCI in system emulation?
> 
> Most probably not. It took me longer than expected to find a ./configure 
> variant that at least allows me to build static qemu-user binaries. Most 
> probably something sneeked in there.
> 
>>
>> Can you simply use TCG to debug your vector instruction issue instead?
> 
> I was using
> 
> ./configure --disable-strip --disable-werror --python=/usr/bin/python3 
> --enable-tcg-interpreter --disable-system --enable-linux-user --static 
> --disable-pie --disable-sdl --disable-gtk --disable-spice 
> --disable-tools --disable-guest-agent --disable-guest-agent-msi 
> --disable-curses --disable-curl --disable-gnutls --disable-gcrypt 
> --disable-nettle --disable-cap-ng --disable-brlapi --disable-mpath 
> --disable-capstone --disable-xen --disable-rdma 
> --extra-ldflags="-Wl,-z,relro -Wl,-z,now" --target-list=s390x-linux-user
> 
> inspired by the Fedora rpm SPEC.
> 
> "--enable-tcg-interpreter" is the relevant bit I blindly copied without 
> thinking about it (in the rpm SPEC, it is wrapped by an ifdef ...)

I thought there was a patch adding a big warning when ./configure is run 
with this option, but I can't find it so maybe we just talked about it.

> Thanks for the hint, will try with --disable-tcg-interpreter
> 
>>
>> Regards,
>>
>> Phil.
>>