Re: [PATCH v6 1/5] kaslr: add kaslr_mem=nn[KMG]@ss[KMG] to specify extracting memory

From: Chao Fan
Date: Mon Jan 15 2018 - 20:17:08 EST


On Mon, Jan 15, 2018 at 02:40:35PM -0800, Randy Dunlap wrote:
>On 01/15/2018 04:40 AM, Chao Fan wrote:
>> In current code, kaslr only has a method to avoid some memory regions,
>> but no method to specify the regions for kaslr to extract. So kaslr
>> may choose the wrong position sometimes, which will cause some other
>> features fail.
>>
>> Here is a problem that kaslr may choose the memory region in movable
>> nodes to extract kernel, which will make the nodes can't be hot-removed.
>> To solve it, we can specify the memory region in immovable node.
>> Create "kaslr_mem=" to store the regions in immovable nodes, where should
>> be chosen by kaslr.
>>
>> Also change the "handle_mem_memmap" to "handle_mem_filter", since
>> it will not only handle memmap parameter now.
>
>Hi,
>
>Are any of the kernel command-line parameters documented anywhere?

Hi,

Sorry for that, not yet.
Because the patchset has been discussed in mailing list for a long time,
and changed for many times, I want to add the document after this
version has been merged or ACKed.

Thanks,
Chao Fan

>
>Thanks.
>
>> Multiple regions can be specified, comma delimited.
>> Considering the usage of memory, only support for 4 regions.
>> 4 regions contains 2 nodes at least, enough for kernel to extract.
>>
>> Signed-off-by: Chao Fan <fanc.fnst@xxxxxxxxxxxxxx>
>> ---
>> arch/x86/boot/compressed/kaslr.c | 73 ++++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 70 insertions(+), 3 deletions(-)
>
>
>--
>~Randy
>
>