Dear Thomas,


Am 21.09.2018 um 00:51 schrieb Thomas Gleixner:

> On Thu, 20 Sep 2018, Paul Menzel wrote:

>> 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.
> 
> Interesting, but I can't spot what causes that.
> 
> Can you please apply the patch below, and provide full dmesg of a seabios
> and a grub boot along with the page table files for each?

I applied the patch on top of 4.19-rc5. Please find all the files attached.


Kind regards,

Paul