Messages in this thread | | | Date | Sun, 15 Mar 2015 10:02:40 -0700 | Subject | Re: [PATCH v4] x86, kaslr: Access the correct kaslr_enabled variable | From | Yinghai Lu <> |
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On Sun, Mar 15, 2015 at 5:18 AM, Minfei Huang <mhuang@redhat.com> wrote: > On 03/15/15 at 12:49am, Yinghai Lu wrote: > It confuses me with the virtual address in function parse_kaslr_setup. > When we are in here(parse_kaslr_setup), we already use the virtual > address, instead of physical address. Is it all right?
setup_data is using physical address to have linked list.
we have setup_arch==>parse_setup_data(), that is way before init_mem_mapping() to have final kernel mapping setup yet.
For 64bit, we may use virtual address with help of early mapping with #PF handler. But 32bit, we don't have that.
So just use early_memmap to get virtual address to access the value.
> > In the other words, using physical address in parse_kaslr_setup is > always a mistake, whatever the kaslr is on or off. >
The problem is: old code just use physical address as value.
Thanks
Yinghai
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