Re: [PATCH] KFENCE: Clarify that sample allocations are not following NUMA or memory policies

[Marco Elver]

On Fri, 24 Jan 2025 at 09:42, Vlastimil Babka <vbabka@xxxxxxx> wrote:
>
> On 1/24/25 09:37, Marco Elver wrote:
> > On Fri, 24 Jan 2025 at 09:13, Vlastimil Babka <vbabka@xxxxxxx> wrote:
> >>
> >> On 1/23/25 23:44, Christoph Lameter via B4 Relay wrote:
> >> > From: Christoph Lameter <cl@xxxxxxxxx>
> >> >
> >> > KFENCE manages its own pools and redirects regular memory allocations
> >> > to those pools in a sporadic way. The usual memory allocator features
> >> > like NUMA, memory policies and pfmemalloc are not supported.
> >>
> >> Can it also violate __GFP_THISNODE constraint? That could be a problem, I
> >> recall a problem in the past where it could have been not honoured by the
> >> page allocator, leading to corruption of slab lists.
> >
> > KFENCE does not sample page allocator allocations. Is kmalloc()
> > allowed to take __GFP_THISNODE?
>
> Yeah and SLUB is honouring it.

Fix: https://lore.kernel.org/all/20250124120145.410066-1-elver@xxxxxxxxxx/

Thanks for pointing it out.