Re: [Qemu-ppc] [Qemu-devel] [PATCH 3/3] configure: Add new target ppc64el-linux-user

[關振德]

On Thu, May 8, 2014 at 8:25 AM, Peter Maydell <address@hidden> wrote:

On 8 May 2014 16:19, Doug Kwan (關振德) <address@hidden> wrote:
> On Thu, May 8, 2014 at 7:41 AM, Tom Musta <address@hidden> wrote:

>> We have TCG targets for PowerPC that are bi-endian. It would be much nicer
>> to have to split
>> user mode by endianness.  If the user loads a BE ELF, then run in BE mode
>> .... a LE ELF,
>> then run in LE mode.
>>
>> I know there is much hand waving in that statement ... but maybe we can do
>> better?  ("we" includes
>> "me" in that statement ... since I offered to Doug to help out with this).

> To do this, we need to fix the elf load.

That is far from the only thing that would need changing.
I really don't recommend trying to do something different
from the norm here.

Isn't LE PPC a different ABI anyway? (ELFv2).

thanks
-- PMM

What else needs to be fixed? I suspect that the user-mode linux kernel interface may also need some work but it worked well enough in practice for us to build glibc and run gcc testsuite.  Yes ELFv2 is a different ABI but it is not complete different from the old one.  A notable change is the removal of function descriptor.  That affect how the user mode start the first instruction and that is addressed in this set of patches.  It would also affect signal handling but user-mode signals do not work at all on PPC64 anyway and the parts that would be affected looks unimplemented.