Re: [Qemu-devel] [Qemu-ppc] [PATCH 1/1] Support ppc64le binfmt registration

[Alexander Graf <agraf@suse.de>]

On 27.08.14 23:35, Peter Maydell wrote:
> On 27 August 2014 22:30, Alexander Graf <agraf@suse.de> wrote:
>>
>>
>> On 27.08.14 21:01, Peter Maydell wrote:
>>> [adding qemu-ppc]
>>>
>>> On 27 August 2014 19:45, Serge E. Hallyn <serge@hallyn.com> wrote:
>>>> Quoting Peter Maydell (peter.maydell@linaro.org):
>>>>> On 27 August 2014 18:55, Serge E. Hallyn <serge@hallyn.com> wrote:
>>>>>> This is a part of a patch proposed by jaejunh at
>>>>>> https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1358268
>>>>>> which enables running ppc64le binaries through qemu-user.
>>>>>
>>>>> I'm confused -- wouldn't these be handled by the existing
>>>>> "ppc64le" support?
>>>
>>>> It looks to me like the point was to add a TARGET_ABI32=y
>>>> version (and I dunno, something about CONFIG_LIBDECNUMBER=y
>>>> for 32-bit).
>>>
>>> Wouldn't that be a "ppc64leabi32" target?
>>
>> There is no LE support for 32bit on PPC :).
> 
> ...in that case what is the original bug reporter actually
> asking for?

Not sure - the only thing that remotely resembles what he's describing
would be if you enable the 32bit personality:

  $ /uname-a.sh
  Linux tempranillo 3.17.0-rc1-2-default+ #1 SMP Thu Jan 1 01:04:00 CET
  1970 ppc64le ppc64le ppc64le GNU/Linux

  $ perl -e 'syscall(136, 8); exec "/uname-a.sh"'
  Linux tempranillo 3.17.0-rc1-2-default+ #1 SMP Thu Jan 1 01:04:00 CET
  1970 ppcle ppcle ppcle GNU/Linux

but that doesn't mean that there is an actual ABI change. The ABI is
still ppc64le, as all binaries are still running in 64bit mode.

So before we add anything to QEMU, I would like to first see someone
point me to kernel patches that actually enable LE on Linux for 32bit
user space. So far I'm not aware of any (and I doubt it makes much sense).


Alex