Re: [Mesa3d-dev] dynamic code generation with gcc

[Gareth H. <ga...@va...>]

Allen Akin wrote:
> 
> On Mon, Mar 12, 2001 at 08:39:30PM -0500, Josh Vanderhoof wrote:
> |               ... You could mprotect() the page after the DMA buffer
> | to PROT_NONE and install a SIGSEGV handler that flushes the buffer if
> | the SIGSEGV was on the end of the DMA buffer.  Then you can just let
> | Vertex3f segfault when it uses the buffer up.
> 
> I haven't used the POSIX signalling system, so please pardon an
> uninformed question.  We couldn't afford to install a short-term
> signal handler each time Vertex3f is called; it would be cheaper just
> to test for overflow.  However, any handler installed long-term by the
> driver could interfere with a handler installed by the application.
> Is there a good way to work around that problem?

I agree.  And yes, just test for buffer overflow :-)  Still, it's a neat
idea.

-- Gareth