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 D4D1AC43334 for ; Mon, 11 Jul 2022 09:13:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231442AbiGKJNi (ORCPT ); Mon, 11 Jul 2022 05:13:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59376 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231337AbiGKJNG (ORCPT ); Mon, 11 Jul 2022 05:13:06 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B84E2F3BB; Mon, 11 Jul 2022 02:09:39 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 76BF26115B; Mon, 11 Jul 2022 09:09:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88EEAC34115; Mon, 11 Jul 2022 09:09:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1657530577; bh=NZfE0H/w5NIGJFcWdjQPXZinzAVGglJvOVXLLc32h1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RmFclwm1L86PTEKxh9ZMAo7mKodTjndzDpJHhgOJdUzuhFmdcs1J8zY3yBdByb6Bq nYyvEY1xBqchXqb+lB0IDMp2Qhb1vkZh9yw0SB9xzSM3RksspQwDhKuehSjKCIXnPR IH52g+BYMkPInmvgigzr3ygnLk9EFVl5axE3RFhw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nick Child , Brian King , Rick Lindsley , "David S. Miller" , Sasha Levin Subject: [PATCH 4.19 19/31] ibmvnic: Properly dispose of all skbs during a failover. Date: Mon, 11 Jul 2022 11:06:58 +0200 Message-Id: <20220711090538.414969149@linuxfoundation.org> X-Mailer: git-send-email 2.37.0 In-Reply-To: <20220711090537.841305347@linuxfoundation.org> References: <20220711090537.841305347@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Rick Lindsley [ Upstream commit 1b18f09d31cfa7148df15a7d5c5e0e86f105f7d1 ] During a reset, there may have been transmits in flight that are no longer valid and cannot be fulfilled. Resetting and clearing the queues is insufficient; each skb also needs to be explicitly freed so that upper levels are not left waiting for confirmation of a transmit that will never happen. If this happens frequently enough, the apparent backlog will cause TCP to begin "congestion control" unnecessarily, culminating in permanently decreased throughput. Fixes: d7c0ef36bde03 ("ibmvnic: Free and re-allocate scrqs when tx/rx scrqs change") Tested-by: Nick Child Reviewed-by: Brian King Signed-off-by: Rick Lindsley Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/ibm/ibmvnic.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index ae3eea4a4213..1463cf4321a8 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -4691,6 +4691,15 @@ static int ibmvnic_reset_init(struct ibmvnic_adapter *adapter) release_sub_crqs(adapter, 0); rc = init_sub_crqs(adapter); } else { + /* no need to reinitialize completely, but we do + * need to clean up transmits that were in flight + * when we processed the reset. Failure to do so + * will confound the upper layer, usually TCP, by + * creating the illusion of transmits that are + * awaiting completion. + */ + clean_tx_pools(adapter); + rc = reset_sub_crq_queues(adapter); } } else { -- 2.35.1