modify_ldt() was declared as an external symbol. Despite the man
page for this syscall telling that there is no wrapper in glibc,
since version 2.1 there actually is, so linking to the glibc
works.
Since modify_ldt() is not a POSIX interface, other libc
implementations do not always provide a wrapper function.
Even glibc headers do not provide a corresponding declaration.
So go the recommended way to call this using syscall().
Signed-off-by: Hans-Werner Hilse <hwhilse@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Before we had SKAS0 UML had two modes of operation
TT (tracing thread) and SKAS3/4 (separated kernel address space).
TT was known to be insecure and got removed a long time ago.
SKAS3/4 required a few (3 or 4) patches on the host side which never went
mainline. The last host patch is 10 years old.
With SKAS0 mode (separated kernel address space using 0 host patches),
default since 2005, SKAS3/4 is obsolete and can be removed.
Signed-off-by: Richard Weinberger <richard@nod.at>
it's x86-only and we have no business playing with it in asm/mmu.h; make
the latter have
struct uml_arch_mm_context arch;
instead of
struct uml_ldt ldt;
and let arch/<subarch>/um/asm/mm_context.h decide what'll be in there.
While we are at it, kill host_ldt.h - it's not needed in part of places
that include it (we want asm/ldt.h in those) and it can be trivially
expanded into the single remaining one.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>