Re: [PATCH v4 4/6] mm/memory-hotplug: add finite retries in offline_pages() if migration fails

[Shakeel Butt <shakeel.butt@linux.dev>]

On Fri, Nov 08, 2024 at 08:00:25PM +0100, David Hildenbrand wrote:
> On 08.11.24 19:56, David Hildenbrand wrote:
> > On 08.11.24 18:33, SeongJae Park wrote:
> > > + David Hildenbrand
> > > 
> > > On Thu, 7 Nov 2024 15:56:12 -0800 Joanne Koong <joannelkoong@gmail.com> wrote:
> > > 
> > > > In offline_pages(), do_migrate_range() may potentially retry forever if
> > > > the migration fails. Add a return value for do_migrate_range(), and
> > > > allow offline_page() to try migrating pages 5 times before erroring
> > > > out, similar to how migration failures in __alloc_contig_migrate_range()
> > > > is handled.
> > > 
> > > I'm curious if this could cause unexpected behavioral differences to memory
> > > hotplugging users, and how '5' is chosen.  Could you please enlighten me?
> > > 
> > 
> > I'm wondering how much more often I'll have to nack such a patch. :)
> 
> A more recent discussion: https://lore.kernel.org/linux-mm/52161997-15aa-4093-a573-3bfd8da14ff1@fujitsu.com/T/#mdda39b2956a11c46f8da8796f9612ac007edbdab
> 
> Long story short: this is expected and documented

Thanks David for the background.

Joanne, simply drop this patch. It is not required for your series.