Re: [Qemu-devel] [PATCH] Handle terminating signals.

["Daniel P. Berrange" <berrange@redhat.com>]

On Tue, Aug 12, 2008 at 09:42:07PM +0200, Gerd Hoffmann wrote:
> M. Warner Losh wrote:
> > In message: <48A1D6A3.4050406@redhat.com>
> >             Gerd Hoffmann <kraxel@redhat.com> writes:
> > : > No, because the program should not attempt to catch SEGV either.
> > : 
> > : Why not?  Can you change your attitude to say "no" without giving
> > : reasons please?
> > 
> > The only portable thing one can do when catching SEGV is terminate the
> > program.  Otherwise, when the signal handler returns, SEGV happens
> > again...
> 
> Returning from the signal handler isn't going to work, sure.  The only
> thing I want do is cleaning up before exiting.
> 
> Most apps never ever have to care about that.  Sometimes there are good
> reasons to attempt a cleanup even for a SEGV though.  The X-Server for
> example attempts to put the gfx card into a sane state then.

The X server often fails to do this cleanup. This is why they're moving
mode setting into the kernel so it can be *reliably* reset. Relying on
a SEGV handler for cleanup is just doomed to fail

Daniel
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