Re: [PATCH v7 02/31] mm: page_alloc: propagate PageReported flag across buddy splits

From: Michael S. Tsirkin

Date: Thu May 14 2026 - 11:47:35 EST


On Thu, May 14, 2026 at 11:41:45AM -0400, Gregory Price wrote:
> On Thu, May 14, 2026 at 11:34:14AM -0400, Michael S. Tsirkin wrote:
> > On Thu, May 14, 2026 at 11:32:26AM -0400, Gregory Price wrote:
> > > > >
> > > > > Maybe mildly out of scope but worth asking: Are there other flags that
> > > > > should be retained/propogated on a split? If so, rather than pass
> > > > > was_reported, should we just take a temporary copy of the page flags and
> > > > > pass them all in?
> > > > >
> > > > > ~Gregory
> > > >
> > > >
> > > > Not that I can see, no.
> > > >
> > >
> > > You do this exact thing again later :]
> > >
> > > https://lore.kernel.org/linux-mm/9a22e0f9bbe1278913754db6df76e291a006181a.1778616612.git.mst@xxxxxxxxxx/
> > >
> > > ~Gregory
> >
> > I mean yes, reported and zeroed) Just zeroed does not exist at this
> > stage in the series.
> >
>
> More of a forward looking question: if we already know we're adding
> was_reported and was_zeroed, maybe we should just pass the page flags
> through entirely and let expand() check them instead of passing it
> through individually.
>
> We end up doing something similar with post_alloc_hook later as well, so
> I'm wondering if there's a general improvement that can be made here.
>
> ~Gregory

sure, will do. do you want a bitwise thing for type safety? or just a
long?