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Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Kaifeng Wang , Dong Chenchen Content-Type: text/plain; charset="UTF-8" With CONFIG_PAGE_POOL_STATS=y, page_pool_recycle_ring_bulk() updates the recycle stats after dropping the producer lock. If it just recycled the last inflight netmems of a pool being destroyed, page_pool_release() can pass its producer-lock barrier and free the pool before recycle_stat_add() runs. Commit fcc680a647ba7 ("page_pool: allow mixing PPs within one bulk") moved this stat update after the unlock. Commit 271683bb2cf32 ("page_pool: Fix use-after-free in page_pool_recycle_in_ring") later added the barrier, but only fixed page_pool_recycle_in_ring(). Move the update back under the lock. Fixes: fcc680a647ba7 ("page_pool: allow mixing PPs within one bulk") Link: https://lore.kernel.org/r/179028939171.2160803.706522228583664641@kernel.org Cc: Kaifeng Wang Cc: Dong Chenchen Assisted-by: LLM Signed-off-by: Mina Almasry --- net/core/page_pool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 08d7f35cf6089..d7c88c0b67e53 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -951,8 +951,8 @@ static void page_pool_recycle_ring_bulk(struct page_pool *pool, } } - page_pool_producer_unlock(pool, in_softirq); recycle_stat_add(pool, ring, i); + page_pool_producer_unlock(pool, in_softirq); /* Hopefully all pages were returned into ptr_ring */ if (likely(i == bulk_len)) base-commit: 11536ee3d3e0b1bd35b6f3f8df55a6053eb0c71d -- 2.56.0.rc1.315.gc6ed9934b7-goog