On 8/9/24 06:48, Kirill A. Shutemov wrote:
> Currently, the kernel only accepts memory in get_page_from_freelist(),
> but there is another path that directly takes pages from free lists -
> __alloc_page_bulk(). This function can consume all accepted memory and
> will resort to __alloc_pages_noprof() if necessary.
>
> Conditionally accepted in __alloc_pages_bulk().
>
> The same issue may arise due to deferred page initialization. Kick the
> deferred initialization machinery before abandoning the zone, as the
> kernel does in get_page_from_freelist().
Is the deferred page init issue an existing problem? In other words,
should it be a separate patch with a Fixes: tag so it can go back to
stable kernels?
Thanks,
Tom
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Acked-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> mm/page_alloc.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index f7bb885aab07..ed62ecd6775f 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -4613,12 +4613,23 @@ unsigned long alloc_pages_bulk_noprof(gfp_t gfp, int preferred_nid,
> goto failed;
> }
>
> + cond_accept_memory(zone, 0);
> +retry_this_zone:
> mark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK) + nr_pages;
> if (zone_watermark_fast(zone, 0, mark,
> zonelist_zone_idx(ac.preferred_zoneref),
> alloc_flags, gfp)) {
> break;
> }
> +
> + if (cond_accept_memory(zone, 0))
> + goto retry_this_zone;
> +
> + /* Try again if zone has deferred pages */
> + if (deferred_pages_enabled()) {
> + if (_deferred_grow_zone(zone, 0))
> + goto retry_this_zone;
> + }
> }
>
> /*
