vmalloc size

Mulyadi Santosa mulyadi.santosa at gmail.com
Mon Jun 25 14:00:47 EDT 2012

Hi.... :)

On Sun, Jun 24, 2012 at 1:32 AM, Subramaniam Appadodharana
<c.a.subramaniam at gmail.com> wrote:
> Hi All,
> I am trying to understand how vmalloc memory is reserved in kernel. In 3.4+
> latest kernel, the default vmalloc size is 240MB.

vmalloc reserved address range, you meant?

>Is this a carveout from
> the 1GiB memory that kernel has?


> In other words can I do a __pa(VMALLOC_START) or __pa(VMALLOC_END)
> or __pa(highmemory) irrespective of the vmalloc size that I request, say
>  doing vmalloc=1G?

uhm....not sure....vmalloc-ed is not physically contigous. Also, it is
set up far after identity mapping setup. So, the value you get from
__pa() IMHO would be likely invalid or has no meaning.


Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com

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