From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7459834F24E; Thu, 1 Oct 2026 01:26:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790817969; cv=none; b=AU7N0+nKTpWIWyf8IaaPHMUN2E1evmDISTbLOStXqGTmfjXiox7BsOvCTFsJX5G3oRHR6k85YCKJAYTyjOb4sCmsUdXL+wNngNNEQ6bA65ZFeLUlnJTc787IhWjbMm9jYRIAm8gjmWGTJ4xY0pAZMVbmQRdOb/Jua+uqZobBHZo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790817969; c=relaxed/simple; bh=WEDGXkCGGeTtmmIndd7KMFiY/AOtuAwb7+AGRTiki30=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=K6pOA/hJxNj0V78zsqGjJdxJhMQjzuW+FgVoEdjq2WeQJriI42bEyI6vQxk+DO2fZogcnLGh3Kl5Q+0fnq3QTnMYJlDCDGGN3PK5X7f2OI6vhsp4PO9bUuZ+HDk1guBtUJ6CVYqrCDv1msB+fEkM59Z3YUZfbhgiA1vkrQfIY78= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=R+2Dl0yw; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="R+2Dl0yw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2FFDA1F000FF; Thu, 1 Oct 2026 01:26:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790817964; bh=twUEiJ/g4lCH2oTGsMXGzEknQ8y+KcaOrNrDuRnsPIg=; h=From:To:Cc:Subject:Date; b=R+2Dl0ywOSYdspW924BWc3j5sJih+z8B7UdUaB5jzWo+T8yZ1vRwPbxPPYnDVtcVQ GEFzgsvcmoHqPxpUwPnjddywIL95aGJ5lq8X17i8j7Un800/4CmfQuxw+lVEEySAyD sCoMe71D2VIwHOhPdP14F5+2FgLzkRQhdXo3R5c3hj77qfq8ffOEDd0dX8B6ZOGIYn d1+dPI4W1j/AwBl1L28TfsEEadh7inq+RM/DDl8/oar57bqVDPpLaS+lZ8FLMnCRSQ uCPVNklFcZ6YAVsLI5QnTX5LT7fbXYaWRQm/6JW+haZEjbq/BrHqdC0IKHpf5ZCtFR elEzikM+Ly5IQ== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, Jakub Kicinski , daniel@iogearbox.net, hawk@kernel.org, john.fastabend@gmail.com, sdf@fomichev.me, ap420073@gmail.com, bpf@vger.kernel.org Subject: [PATCH net] net: make dev_xdp_sb_prog_count() see programs attached through a link Date: Wed, 30 Sep 2026 18:25:59 -0700 Message-ID: <20261001012559.297751-1-kuba@kernel.org> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit ethtool refuses to enable tcp-data-split on a device running a single-buffer XDP program (which can't deal with the payload landing in a separate buffer). dev_xdp_sb_prog_count() only looks at xdp_state[].prog though, ignoring bpf_link integration. Get the prog pointer from dev_xdp_prog(), which will consult both. bpf_xdp_link_update() needs a bit of a touch-up, too, since ethtool calls dev_xdp_sb_prog_count() with just the instance lock (for ops-locked devices) - we now have to make sure the link updates happen under that lock. Spotted by AI while reviewing the XDP propagation series, verified and tested on netdevsim with a C test along these lines: link = bpf_program__attach_xdp(prog, ifindex); system("ethtool -G eth0 tcp-data-split on") Fixes: 197258f0ef68 ("net: ethtool: add hds_config member in ethtool_netdev_state") Signed-off-by: Jakub Kicinski --- CC: daniel@iogearbox.net CC: hawk@kernel.org CC: john.fastabend@gmail.com CC: sdf@fomichev.me CC: ap420073@gmail.com CC: bpf@vger.kernel.org --- net/core/dev.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 79be99b52f20..030c444aee45 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10367,13 +10367,15 @@ EXPORT_SYMBOL_GPL(dev_xdp_prog_count); u8 dev_xdp_sb_prog_count(struct net_device *dev) { + struct bpf_prog *prog; u8 count = 0; int i; - for (i = 0; i < __MAX_XDP_MODE; i++) - if (dev->xdp_state[i].prog && - !dev->xdp_state[i].prog->aux->xdp_has_frags) + for (i = 0; i < __MAX_XDP_MODE; i++) { + prog = dev_xdp_prog(dev, i); + if (prog && !prog->aux->xdp_has_frags) count++; + } return count; } @@ -10753,11 +10755,12 @@ static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, xdp_link->flags, new_prog); + if (!err) + old_prog = xchg(&link->prog, new_prog); netdev_unlock_ops(xdp_link->dev); if (err) goto out_unlock; - old_prog = xchg(&link->prog, new_prog); bpf_prog_put(old_prog); out_unlock: -- 2.55.0