Hi,
I am trying to integrate binfmt_xout.c into kernel 2.4 as part of the
linux-abi project (formerly known as iBCS). For old Xenix 286 binaries the
lcall7 gate needs to part of the LDT.
In kernels 2.0 sys_modify_ldt(0,...) used to return the default_ldt (with
lcall7 gate) if there were no segments set up. This behaviour changed in
kernels 2.2 . As a result of a discussion with Linus, David Bruce wrote a
patch for binfmt_xout.c tweaking with gdt and current->tss.ldt to get the
address of default_ldt. This patch does not work any more with kernels 2.4
as tss vanished from task_struct.
I do see 4 ways to cope with this problem:
a) extend sys_modify_ldt with a function to retrieve the default_ldt. I did
this for testing (see attached diff for arch/i386/kernel/ldt.c ).
b) do some work an Davids patch but this is kind of magic for me :-)
(see attached default_ldt patch)
c) loose the option to compile binfmt_xout (and the rest of linux-abi) as
module and simply use the symbol default_ldt. I dint't try that.
d) Forget about those old fashioned 286 binaries. This option will make some
linux users feel sad, as they run these progs for their daily business.
Joerg
-- ------------------------------------------------------------------------------ Joerg Ahrens _/ Koenigsberger Strasse 32 _/_/ 31226 Peine _/ _/ Tel.: 05171/57308 _/ _/_/_/_/ e-mail: joerg@hydrops.han.de _/_/_/_/ _/ ------------------------------------------------------------------------------
This archive was generated by hypermail 2b29 : Fri Jun 15 2001 - 21:00:11 EST