Re: [PATCH] mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing

From: Linus Torvalds
Date: Sun Sep 25 2016 - 16:52:44 EST


I was kind of assuming this would go through the normal channels for
THP patches, but it's been two weeks...

Can I have an ACK from the involved people, and I'll apply it
directly.. Mel? Rik?

Linus

On Sun, Sep 25, 2016 at 11:47 AM, Lorenzo Stoakes <lstoakes@xxxxxxxxx> wrote:
> Just a quick ping on this, let me know if you need anything more from me!
>
> Thanks, Lorenzo
>
> On Sun, Sep 11, 2016 at 11:54:25PM +0100, Lorenzo Stoakes wrote:
>> The NUMA balancing logic uses an arch-specific PROT_NONE page table flag defined
>> by pte_protnone() or pmd_protnone() to mark PTEs or huge page PMDs respectively
>> as requiring balancing upon a subsequent page fault. User-defined PROT_NONE
>> memory regions which also have this flag set will not normally invoke the NUMA
>> balancing code as do_page_fault() will send a segfault to the process before
>> handle_mm_fault() is even called.
>>