Re: Crashes if running WordPerfect 5.1

[Stas Sergeev <stsp@aknet.ru>]

Hello.

Bart Oldeman wrote:
> I think I would personnally like it best if there wasn't a pagealloc
> either, but just multiple fd's.
Yes, I already recognized that as a
good idea even for mapfile (esp. now
on /dev/shm), so the first step I was
going to take, is to avoid pagemalloc
for mapfile.

> That way you can have only one mapping
> backend, it just differs in what the fd opens (i.e. /dev/zero or a
> temporary file, or perhaps shm_open), and we don't need the mremap 
> trick.
Also we may not need the multiple
mapping backends amymore then, since
the only difference would be how the
fd is being opened.

> alloc_mapping opens a /dev/zero
Was it already verified that this can
be shared without mremap?

  or tmpfile -- the fd will be remembered
> (linked list connecting it to the memory address)
Yes, somewhat resembling the tracking
of kmem mappings in mapping.c I think.
The problem is that the run-time check
for NPTL will not help, we need a
compile-time check if we want to use
open_shm(). That will mean the binary-
distributed dosemu will either have
open_shm() disabled, or not working
with linuxthreads. Or maybe dlopen()
librt? No fun... How's your ptrace patch
going? It could really help in resolving
this mess.