Re: [PATCH] DAX: warn when kmem regions are truncated for memory block alignment.

[David Hildenbrand]

On 01.04.25 17:16, Gregory Price wrote:
> On Tue, Apr 01, 2025 at 04:50:40PM +0200, David Hildenbrand wrote:
> > Oh, you mean with the whole memmap_on_memory thing. Even with that, using
> > 2GB memory blocks would only fit a single 1GB memory block ... and it
> > requires ZONE_NORMAL.
> >
> > For ordinary boot memory, the 1GB behavior should be independent of the
> > memory block size (a 1GB page can span multiple blocks as long as they are
> > in the same zone), which is the most important thing.
> >
> > So I don't think it's a concern for DAX right now. Whoever needs that, can
> > disable the memmap_on_memory option.
>
> If we think it's not a major issue then I'll rebase onto latest and push
> a v9.  I think there was one minor nit left.
>
> I suppose folks can complain to their vendors about alignment if they
> don't want 60000 memoryN entries on their huge-memory-systems.
>
> Probably we still want this warning?  Silent truncation still seems
> undesirable.

Yes, it's valuable I think. But should it be a warning or rather an info?

--
Cheers,

David / dhildenb