-----Original Message-----
From: Russell King - ARM Linux [mailto:linux at arm.linux.org.uk]
Sent: Friday, January 03, 2014 9:47 AM
To: Gioh Kim
Cc: 'Baruch Siach'; linux-mm at kvack.org; 'linux-arm-kernel'; 'HyoJun Im'
Subject: Re: ARM: mm: Could I change module space size or place modules in
vmalloc area?

On Fri, Jan 03, 2014 at 09:39:31AM +0900, Gioh Kim wrote:

quoted

Thank you for reply.

quoted

-----Original Message-----
From: Baruch Siach [mailto:baruch at tkos.co.il]
Sent: Thursday, January 02, 2014 7:14 PM
To: Gioh Kim
Cc: Russell King; linux-mm at kvack.org; linux-arm-kernel; HyoJun Im
Subject: Re: ARM: mm: Could I change module space size or place
modules in vmalloc area?

Hi Gioh,

On Thu, Jan 02, 2014 at 07:04:13PM +0900, Gioh Kim wrote:

quoted

I run out of module space because I have several big driver modules.
I know I can strip the modules to decrease size but I need debug
info

now.

Are you sure you need the debug info in kernel memory? I don't think
the kernel is actually able to parse DWARF. You can load stripped
binaries into the kernel, and still use the debug info with whatever

tool you have.

quoted

I agree you but driver developers of another team don't agree.
I don't know why but they say they will strip drivers later :-( So I
need to increase modules space size.

ARM can only branch relatively within +/- 32MB.  Hence, with a module
space of 16MB, modules can reach up to a maximum 16MB into the direct-
mapped kernel image.  As module space increases in size, so that figure
decreases.  So, if module space were to be 40MB, the maximum size of the
kernel binary would be 8MB.

You want to look at a line similar to this:

      .text : 0xc0008000 - 0xc031eda0   (3164 kB)

Also, note this:

    modules : 0xbf000000 - 0xc0000000   (  16 MB)

If the difference between the lowest module address (0xbf000000) and the
highest of .text is greater than 32MB, it's impossible to load modules -
they will fail to link.

What is the size of your kernel text? (show us the line(s) like the

above.)

My kernel size is about 8MB as below.
[    0.000000]     modules : 0x7f000000 - 0x80000000   (  16 MB)
[    0.000000]       .text : 0x80008000 - 0x8085d2b0   (8533 kB)

I think I can increase the modules space size into 20MB.
Thanks for your reply.

Thanks.

--
FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up.  Estimation in
database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad.
Estimate before purchase was "up to 13.2Mbit".