Re: [Qemu-devel] Alpha linux-user support

[Laurent Desnogues]

On Wed, Nov 5, 2008 at 11:03 PM, Vince Weaver <address@hidden> wrote:
>
> First, I found a bug in the alpha emulation of the "ret" instruction, see a
> separate e-mail to the list.
[...]
> I've attached my simple assembly program I am working with.  It should print
> hello world, but doesn't because the address passed to the write syscall is
> wrong.  I can't easily track down where things are going wrong though
> because the gdbstub doesn't work for alpha.  Does anyone know the status of
> that?

After applying your ret patch, it works for me on an x86_64 platform.
However the first callsys instruction fails on ia32 and returns EFAULT
(bad address).

In fact what happens looks like a problem of 64 -> 32 bit mapping:
page_check_range fails (called by access_ok which is called by
lock_user in do_syscall).  It doesn't like the 0x120010100 address.


Laurent