Re: Question about signal syscalls !

["Franck Bui-Huu" <vagabon.xyz@gmail.com>]

On 2/2/07, David Daney <ddaney@avtrex.com> wrote:
> Franck Bui-Huu wrote:
> > David Daney wrote:
> >> The entire user context (i.e. the value of *all* registers) is replaced
> >> with the values stored in the sigcontext structure on the caller's
> >> stack.  If all registers are being restored from the sigcontext, then
> >> there is no need to save the current values of the registers, because
> >> they will never be used.
> >>
> >
Again, why do you think that all values of the registers are saved on
sys_sigreturn() ?


> > And now I'm starting to think that we don't need to save static regs in
> > setup_sigcontext() either...
> >
> All registers *must* be saved in the sigcontext.  That is part of the
> contract the kernel has with user code.
I'm just talking about _static_ registers which are s0-s7...

> On return from an asynchronous signal, *all* registers must contain the
> same values they had before the process was interrupted.
yes I agree and I've never said the contrary.
--
              Franck