Alan Cox <alan@lxorguk.ukuu.org.uk> writes:
> > The layout of the sys_call_table is totally architecture dependant. The
> > question to ask here is why do you need to use it? Modifying it to hook
> > into syscalls is frowned upon.
>
> And potentially unsafe (think about caching, and non atomic writes on
> some platforms)
It is ATM impossible to make a module that patches sys_call_table safe against
module unload races. The only way is to put a stub into the main kernel
that manages the module counters and calls a separate hook (i.e. as done
by nfsd's syscall)
[Introducing quiescent states in module unloading would probably fix that,
as it has been discussed for a long time now, but I lost hope that it'll ever
get implemented in the main kernel]
Other than that on some weird architectures like IA64 it can get quite
complicated to patch the syscall table.
-Andi
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This archive was generated by hypermail 2b29 : Fri Aug 31 2001 - 21:00:30 EST