On Tue, Aug 13, 2024 at 2:25 AM David Hildenbrand <david@xxxxxxxxxx> wrote:
>
> On 12.08.24 21:24, Suren Baghdasaryan wrote:
> > During CMA activation, pages in CMA area are prepared and then freed
> > without being allocated. This triggers warnings when memory allocation
> > debug config (CONFIG_MEM_ALLOC_PROFILING_DEBUG) is enabled. Fix this
> > by marking these pages not tagged before freeing them.
> >
> > Fixes: d224eb0287fb ("codetag: debug: mark codetags for reserved pages as empty")
> > Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx # v6.10
> > ---
> > changes since v1 [1]
> > - Added Fixes tag
> > - CC'ed stable
> >
> > [1] https://lore.kernel.org/all/20240812184455.86580-1-surenb@xxxxxxxxxx/
> >
> > mm/mm_init.c | 10 ++++++++++
> > 1 file changed, 10 insertions(+)
> >
> > diff --git a/mm/mm_init.c b/mm/mm_init.c
> > index 75c3bd42799b..ec9324653ad9 100644
> > --- a/mm/mm_init.c
> > +++ b/mm/mm_init.c
> > @@ -2245,6 +2245,16 @@ void __init init_cma_reserved_pageblock(struct page *page)
> >
> > set_pageblock_migratetype(page, MIGRATE_CMA);
> > set_page_refcounted(page);
> > +
> > + /* pages were reserved and not allocated */
> > + if (mem_alloc_profiling_enabled()) {
> > + union codetag_ref *ref = get_page_tag_ref(page);
> > +
> > + if (ref) {
> > + set_codetag_empty(ref);
> > + put_page_tag_ref(ref);
> > + }
> > + }
>
> Should we have a helper like clear_page_tag_ref() that wraps this?
With this one we have 3 instances of this sequence, so it makes sense
to have a helper. I'm going to send a v3 with 2 patches - one
introducing clear_page_tag_ref() and the next one adding this
instance.
Thanks for the suggestion, David!
>
> --
> Cheers,
>
> David / dhildenb
>
