Dear Thomas,


As always, thank you for the quick response.

Am 19.09.2018 um 10:09 schrieb Thomas Gleixner:

> On Wed, 19 Sep 2018, Paul Menzel wrote:
>>
>> With Linux 4.19-rc4+ and `CONFIG_DEBUG_WX=y`, I see the message below on
>> the ASRock E350M1.
>>
>>> [    1.813378] Freeing unused kernel image memory: 1112K
>>> [    1.818662] Write protecting the kernel text: 8708k
>>> [    1.818987] Write protecting the kernel read-only data: 2864k
>>> [    1.818989] NX-protecting the kernel data: 5628k
>>> [    1.819265] ------------[ cut here ]------------
>>> [    1.819272] x86/mm: Found insecure W+X mapping at address
>>> (ptrval)/0xc00a0000
>>
>> I do not notice any problems with the system, but maybe something can be done
>> to get rid of these.
> 
> Can you please enable CONFIG_X86_PTDUMP and provide the output of the files
> in /sys/kernel/debug/page_tables/ ?

By accident, I noticed that this issue does not happen with GRUB as 
coreboot payload, and only with SeaBIOS. (I only tested on the ASRock 
E350M1.) A coreboot developer said, that SeaBIOS does not do mapping though.

Please find attached the files from SeaBIOS and GRUB.


Kind regards,

Paul