Messages in this thread |  | | From | (Alan Cox) | Subject | Re: "Exception at ..." with 2.1.9 and 2.1.10 kernels | Date | Wed, 20 Nov 1996 19:50:27 +0000 (GMT) |
| |
> It was a null pointer being passed. This does bring up a minor question of > whether a null pointer should be handled here or higher up.
There is a reason we handle things the way we do. In 2.0.x there was a routine that verified addresses were ok. It stomped off into the page tables, checked entries and said Yay or Nay. The hardware can do this except for the fact you take the 'Oi stop that' message (the exception) when you access that byte. 2.1.x uses this even though its tricker as verify_area() took valuable CPU time and Linus decided to be cleverer than 99% of other OS vendors again.
Alan
|  |