Re: /dev/kmem /dev/mem PATCH for kernel 2.1.15

Marcin Dalecki (dalecki@sub994.sub.uni-goettingen.de)
Mon, 16 Dec 1996 15:07:36 +0100 (MET)


On Mon, 16 Dec 1996, Hans Lermen wrote:

> I guess you mixed the things a bit ;-)
>
> MAJOR 1, MINOR 0 /dev/ram0 == block device, == ramdisk
> ^^^^^ ^^^^
> MAJOR 1, MINOR 1 /dev/mem == character device, == memory device
>

No no I didn't. Please take a look at the patch. the major 1, minor 0
*character* device wasn't registered thus far anywhere. And the ram was
related to the (read|write)_ram ending for the corresponding realization
routines. The routines didn't anything. They just returned -EIO!

> > The virtual address space should be
> > accessed by /dev/kmem (see man 2 kmem or man 2 mem for confirmance.)
>
> ... better see linux/Documentation/devices.txt:
>
> 1 char Memory devices
> 1 = /dev/mem Physical memory access
> 2 = /dev/kmem Kernel virtual memory access
>
> ( this always is the actual source for device assignments )

Yes. That's exactly what the patch is supposed to correct!!!!

Plase just try for example ksyms -m after loading of some module with (it
works again) and without (it doesn't) the patch. If still in doubt, take a
look at the real ksysm code in insmod.c (at the end) from
modules-2.1.13.tar.gz.

Marcin