On 04/14/2015 06:16 AM, Alexander Kuleshov wrote:
Hello All,

I'm reading x86_64 source code and trying to understand where are
fixmaps space in the virtual memory space. If I understand correctly
(but i'm really not sure about it), fixmap space is after vsyscall
space. As Documentation/x86/x86_64/mm.txt says vsyscall virtual space
is:

ffffffffff600000 - ffffffffffdfffff (=8 MB) vsyscalls

With 'earlyprintk' i got FIXADDR_START and FIXADDR_TOP and they are:

FIXADDR_START -  0xffffffffff779000L
FIXADDR_TOP     -  0xffffffffff7ff000L

with these addressess FIXADDR_START/FIXADDR_TOP overlap vsyscalls
area. Is it correct case that fixmaps are in vsyscal virtual memory
space or I'm wrong somewhere?

It's the other way around. vsyscalls are in the fixmap. I should fix the docs.

--Andy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to