Re: [PATCH] Fix mmap_kmem (was: [question] What's the difference between /dev/kmem and /dev/mem)

Arjan van de Ven
2005-08-12T17:57:04Z

On Fri, 2005-08-12 at 18:54 +0200, Andi Kleen wrote:
> Linus Torvalds <torvalds@osdl.org> writes:
> >
> > I'm actually more inclined to try to deprecate /dev/kmem.. I don't think
> > anybody has ever really used it except for some rootkits.
>
> I don't think that's true.

got any examples ?

>
> > So I'd be perfectly happy to fix this, but I'd be even happier if we made
> > the whole kmem thing a config variable (maybe even default it to "off").
>
> Acessing vmalloc in /dev/mem would be pretty awkward. Yes it doesn't
> also work in mmap of /dev/kmem, but at least in read/write.
> There are quite a lot of scripts that use it for kernel debugging
> like dumping variables. And for that you really want to access modules
> and vmalloc. And it's much easier to parse than /proc/kcore

but you can stick gdb on /proc/kcore...