From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07058C433F5 for ; Fri, 21 Jan 2022 12:00:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350293AbiAUMAq (ORCPT ); Fri, 21 Jan 2022 07:00:46 -0500 Received: from mga01.intel.com ([192.55.52.88]:36384 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350222AbiAUMAm (ORCPT ); Fri, 21 Jan 2022 07:00:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642766442; x=1674302442; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=a186eXNPkax1sNYDYG0nbWrG9jTaVQGIxQl2OdizbmY=; b=kP5xFdiE7GsAGKJwMF4agfsELMeO9Et47MPIjkLkFGLxHbQYri1XZl9U YlHit1zsJWndvVHHpyyqavnMT9x3u5RAHWoSPQlljd3DHdyLHhFeLlNZ6 U/YUZzSQSZ/Kt74DFNvsxUSJDprmUgIWm5juArRUwgjN7KBj0zSdK498n IuYMw8TIXjRtKaJ4fEYObgoEu4Sna3RhR/DvIGW+ztZgx4I+P6J1M46p/ D4XwSgoyY04J24dduAChDVspKmwgI7KOkKE1rE1kZ2oIKmFg7qa408Yz9 C0EXAyehNuv/29zlBoCqbq4iWDmlNxg+ArqDKAUDhuwvK7I/OSQSTVJ2g Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10233"; a="270059003" X-IronPort-AV: E=Sophos;i="5.88,304,1635231600"; d="scan'208";a="270059003" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jan 2022 04:00:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,304,1635231600"; d="scan'208";a="475924984" Received: from boxer.igk.intel.com ([10.102.20.173]) by orsmga003.jf.intel.com with ESMTP; 21 Jan 2022 04:00:38 -0800 From: Maciej Fijalkowski To: bpf@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net Cc: netdev@vger.kernel.org, magnus.karlsson@intel.com, alexandr.lobakin@intel.com, Maciej Fijalkowski Subject: [PATCH bpf-next v3 5/7] ice: xsk: avoid potential dead AF_XDP Tx processing Date: Fri, 21 Jan 2022 13:00:09 +0100 Message-Id: <20220121120011.49316-6-maciej.fijalkowski@intel.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20220121120011.49316-1-maciej.fijalkowski@intel.com> References: <20220121120011.49316-1-maciej.fijalkowski@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commit 9610bd988df9 ("ice: optimize XDP_TX workloads") introduced @next_dd and @next_rs to ice_tx_ring struct. Currently, their state is not restored in ice_clean_tx_ring(), which was not causing any troubles as the XDP rings are gone after we're done with XDP prog on interface. For upcoming usage of mentioned fields in AF_XDP, this might expose us to a potential dead Tx side. Scenario would look like following (based on xdpsock): - two xdpsock instances are spawned in Tx mode - one of them is killed - XDP prog is kept on interface due to the other xdpsock still running * this means that XDP rings stayed in place - xdpsock is launched again on same queue id that was terminated on - @next_dd and @next_rs setting is bogus, therefore transmit side is broken To protect us from the above, restore the default @next_rs and @next_dd values when cleaning the Tx ring. Signed-off-by: Maciej Fijalkowski --- drivers/net/ethernet/intel/ice/ice_txrx.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index e661d0e45b9b..bfb9158b10a4 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -173,6 +173,9 @@ void ice_clean_tx_ring(struct ice_tx_ring *tx_ring) tx_ring->next_to_use = 0; tx_ring->next_to_clean = 0; + tx_ring->tx_thresh = ice_get_tx_threshold(tx_ring); + tx_ring->next_dd = tx_ring->tx_thresh - 1; + tx_ring->next_rs = tx_ring->tx_thresh - 1; if (!tx_ring->netdev) return; -- 2.33.1