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

[David Hildenbrand <david@redhat.com>]

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 ...)

Thanks for the hint, will try with --disable-tcg-interpreter

> 
> Regards,
> 
> Phil.
> 


-- 

Thanks,

David / dhildenb