Re: [PATCH 1/1] alloc_tag: mark pages reserved during CMA activation as not tagged

[Suren Baghdasaryan]

On Mon, Aug 12, 2024 at 11:44 AM Suren Baghdasaryan <surenb@xxxxxxxxxx> 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.

This should also have:

Fixes: d224eb0287fb "codetag: debug: mark codetags for reserved pages as empty"

>
> Signed-off-by: Suren Baghdasaryan <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);
> +               }
> +       }
>         __free_pages(page, pageblock_order);
>
>         adjust_managed_page_count(page, pageblock_nr_pages);
>
> base-commit: d74da846046aeec9333e802f5918bd3261fb5509
> --
> 2.46.0.76.ge559c4bf1a-goog
>