Re: [PATCH] arm64: mm: support setting page attributes for debug situation

[Yunfeng Ye]

On 2020/1/16 19:09, Will Deacon wrote:
> On Fri, Jan 10, 2020 at 03:47:41PM +0800, yeyunfeng wrote:
>> When rodata_full is set or pagealloc debug is enabled, block mappings or
>> contiguou hints are no longer used for linear address area. Therefore,
>> support setting page attributes in this case is useful for debugging
>> memory corruption problems.
>>
>> Signed-off-by: Yunfeng Ye <yeyunfeng@xxxxxxxxxx>
>> ---
>>  arch/arm64/mm/pageattr.c | 18 ++++++++++++++----
>>  1 file changed, 14 insertions(+), 4 deletions(-)
> 
> Although I can kind of see what you're getting at, I'm not keen on merging
> this without a user. If you're just referring to random debug hacks, then I
> think this change could be part of those too.
> 
Ok, thanks, I think when pagealloc debug is enabled, it is better not limited
to the vmap area only. and when kernel memory corruption problems happen, it's
useful to call set_memory_ro() function to debug these problem.

> Will
> 
> .
>