Re: [PATCH v4] mm: page_alloc: add missing hooks to bulk allocation path

From: Zi Yan

Date: Tue Sep 08 2026 - 22:20:31 EST


On Tue Sep 8, 2026 at 6:23 AM EDT, Qiqi Liu wrote:
> The bulk allocation path in alloc_pages_bulk_noprof() currently misses
> trace_mm_page_alloc() and kmsan_alloc_page() calls, leaving bulk-allocated
> pages invisible to ftrace/BPF/perf and leaving KMSAN shadow memory stale.
>
> Add both calls in the bulk loop to match the standard allocation path,
> placing them before set_page_refcounted() for consistency. The gfp mask
> passed to kmsan_alloc_page() is stripped of __GFP_RECLAIM because the
> bulk loop runs under the PCP spinlock, and KMSAN's stack depot allocation
> must not sleep.
>
> Both are no-ops when their respective features are disabled, so there
> is no overhead in production kernels.
>
> Suggested-by: Gregory Price <gourry@xxxxxxxxxx>
> Signed-off-by: Qiqi Liu <liuqiqi@xxxxxxxxxx>
> ---
> mm/page_alloc.c | 2 ++
> 1 file changed, 2 insertions(+)
>

LGTM.

Reviewed-by: Zi Yan <ziy@xxxxxxxxxx>

BTW, please send new versions in a new thread instead of replying to the
old one. Thanks.

--
Best Regards,
Yan, Zi