From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793826893; b=T1YJKlgVZrzArj74DrMj9x+FZvPJawnHx83qJ9vRlnq/sSmHFPLT/MOs2cOXRhFL6QNK 58QGRyonAevaU8VzHPP1NwqOyYSwipca/14FkQN45neQWFFnFtT5KYraEWeMOTmGB3gF6 m+2NhvNcN+EtaTcmqruBhskU/X5UcFNiO+NA47U/sxdcC5dYRWGwgT7XkxDtrxRKm/RbX TIRTTPmGwxPAX7pcmlDuRojKucq791yxfV5J/I8aHSpEp8q91PV1iS9vd1wcIxrK/Qh2Q oYdcwnrMQQT8It9h+bAqe6KViU99DwfrKWpCosQmQE4jb32tpBpLyIHYe8t9hF1uEGg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793826893; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=JYWJlyYIG0M8QxclLsh8thjYd5ecaC2qgMkpuLl4nTs=; b=S4U1GVwCARATYTyWWkq7SnaeSQyYb7Vo8XrcziOe5K1EORftodO6e36VE91whuqhJwQq O4m4IBJgvt1ALDxo2KYrkvBOMXpFl+JqP7qL3WP6KcxGSN/U/7+4u/gEXRT1FTlf7ogL2 /r5gJiy2eeCaXA81t+QeSOv5K8POlwNarfZkyYltbMF16L1FTU9F+r2I0H+C9N8afmfSz KumwydxASb8J0m0OZnVA1spiKAZ8MxHwYzKRfZlUshR49CDqwOpUIW/buao0FrcVMwn0E GBdvhq+dMSty31U5gXXcJMBL3Z85Ul1L5zqho6f3+1k1D+A7n0zER5dAZkvWQn4NjjQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nGwxhna2; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A56DF6070760; Wed, 4 Nov 2026 21:14:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nGwxhna2 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32F211F000C1; Wed, 4 Nov 2026 21:14:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793826893; bh=JYWJlyYIG0M8QxclLsh8thjYd5ecaC2qgMkpuLl4nTs=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=nGwxhna20M7O/iLPC9ftztdz7IEi9uchsNvc4J07jorKAB/Q9t4Pi2K1u2oFYJBvH 6oTvMYMLerHXK74ec5w6j9zwvoE3zXjY9PZk8ipzugtK6UtAqyjO3ccnbeWuFr1nA5 Rp5YaWKJy9N0YGI3jTkNnqr/Xhh6izoAFijZThB13ZKCJPRkmFNGbXmJ5DZ++OAMVo uKfIno04uylCWc/po/x8d8+/EEnKxiOt0QfwuajYRh35IzG4vPCJLWZSxTMIcjYyZ6 4OSiM1rPY1197ZRcdsDJKHlGgHFzW2raQEwJNs8YWqcuMLuyqLINH8wWa2RvOsCLKZ QiP9EX5RHuRfg== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH net-next v1 3/5] net: datagram: refcount page_pool frags in zerocopy_fill_skb_from_iter() Reply-To: sashiko-reviews@lists.linux.dev To: "Mina Almasry" , virtualization@lists.linux.dev, linux-rdma@vger.kernel.org Cc: "Michael S. Tsirkin" , "Eugenio Perez" In-Reply-To: <20261103211424.127627-4-almasrymina@google.com> References: <20261103211424.127627-1-almasrymina@google.com> <20261103211424.127627-4-almasrymina@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 04 Nov 2026 21:14:52 +0000 X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > When an application maps order-0 page_pool RX fragments into user space > via TCP_ZEROCOPY_RECEIVE and forwards that mapped address into TX > sendmsg(MSG_ZEROCOPY), zerocopy_fill_skb_from_iter() pins the pages via > iov_iter_get_pages2() (which increments page->_refcount) while > skb_release_data() releases fragments via netmem_dec_ref(). >=20 > Acquire each fragment reference via netmem_inc_ref() when attaching a > fragment in zerocopy_fill_skb_from_iter() and release the corresponding > GUP page->_refcount reference via the existing batched page_ref_sub() > path so the TX SKB fragment reference pairs with netmem_dec_ref() in > skb_release_data() once netmem_inc_ref() and netmem_dec_ref() handle > page_pool netmems. >=20 > Signed-off-by: Mina Almasry Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261103211424.1276= 27-1-almasrymina@google.com?part=3D3