Subject: There is a hole in my ELF
To: None <firstname.lastname@example.org>
From: Johan Danielsson <email@example.com>
Date: 08/10/1998 15:52:51
While hacking on an ELF aware modload, I stumbled on this GNU-ld
feature (from elf.sc):
/* Adjust the address for the data segment. We want to adjust up to
the same address within the page on the next page up. */
Ok, fine. But why? I can imagine cases where you'd want the data
segment to start at the next page, but why offset it into the next
page? IRIX ld seems to put things at the next page boundary.
And why is MAXPAGESIZE 1MB on alpha?
I guess this isn't a problem with ordinary programs, but with the
present a.out-centric lkm interface, quite a lot of kernel memory gets
wasted without doing ugly tricks.
Thinking about it, this might perhaps be a tool-chain issue...