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charset="UTF-8" X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 38D6A4000C X-Stat-Signature: xrhwz31sudwkxisxy4hgfdmuukhqf5dp X-Rspam-User: X-HE-Tag: 1757460861-321348 X-HE-Meta: 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 a1tEWUlC 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: When freeing "tail" pages of a non-compount high-order page, we properly subtract the allocation tag counters, however later when these pages are released, alloc_tag_sub() will issue warnings because tags for these pages are NULL. This issue was originally anticipated by Vlastimil in his review [1] and then recently reported by David. Prevent warnings by marking the tags empty. [1] https://lore.kernel.org/all/6db0f0c8-81cb-4d04-9560-ba73d63db4b8@suse.cz/ Suggested-by: David Wang <00107082@163.com> Signed-off-by: Suren Baghdasaryan --- mm/page_alloc.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 1760346bbd24..d21a411e807e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5240,9 +5240,16 @@ static void ___free_pages(struct page *page, unsigned int order, __free_frozen_pages(page, order, fpi_flags); else if (!head) { pgalloc_tag_sub_pages(tag, (1 << order) - 1); - while (order-- > 0) + while (order-- > 0) { + /* + * The "tail" pages of this non-compound high-order + * page will have no code tags, so to avoid warnings + * mark them as empty. + */ + clear_page_tag_ref(page + (1 << order)); __free_frozen_pages(page + (1 << order), order, fpi_flags); + } } } -- 2.51.0.384.g4c02a37b29-goog