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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A656BC2D0DB for ; Wed, 22 Jan 2020 09:47:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 724272468A for ; Wed, 22 Jan 2020 09:47:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579686424; bh=vaofyrLwmOJJ91LZD0XAQw7z34u1sziwFQ2dIIgGd7o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BxenKUUSzREM+icrk9+sYo8f93brK3wWyTdYOic1VgV86cVH8xS79b+o0u0NlZTw6 6DEGeoM1DO8M7Gmp5NBh2JJfm9HjOFTgDm0vyMtww4GBOTdEArpQhb08hX2caCruY+ xxHxWI0Af41zQVl+Y3LypDzPgW98N/2k6wZrdWTg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731615AbgAVJrD (ORCPT ); Wed, 22 Jan 2020 04:47:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:34702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387770AbgAVJmn (ORCPT ); Wed, 22 Jan 2020 04:42:43 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8704A24689; Wed, 22 Jan 2020 09:42:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579686163; bh=vaofyrLwmOJJ91LZD0XAQw7z34u1sziwFQ2dIIgGd7o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UetGTManXrFFxctSzCY6QYDOtZscZkioOCJEOhjvoX9i91FlWOp+BjN+POj+m/v7B /h7aVRSNhdelGX6/fHDacggZB97G25WSY6TL2oZOti1lmZ1zJoBKbwiC3BtvHZvmSL pxws3sknN8X4smNtuwS8oyFlUECmi96mkaxfDIPE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yonglong Liu , "David S. Miller" Subject: [PATCH 4.19 070/103] net: hns: fix soft lockup when there is not enough memory Date: Wed, 22 Jan 2020 10:29:26 +0100 Message-Id: <20200122092813.954240644@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200122092803.587683021@linuxfoundation.org> References: <20200122092803.587683021@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yonglong Liu [ Upstream commit 49edd6a2c456150870ddcef5b7ed11b21d849e13 ] When there is not enough memory and napi_alloc_skb() return NULL, the HNS driver will print error message, and than try again, if the memory is not enough for a while, huge error message and the retry operation will cause soft lockup. When napi_alloc_skb() return NULL because of no memory, we can get a warn_alloc() call trace, so this patch deletes the error message. We already use polling mode to handle irq, but the retry operation will render the polling weight inactive, this patch just return budget when the rx is not completed to avoid dead loop. Fixes: 36eedfde1a36 ("net: hns: Optimize hns_nic_common_poll for better performance") Fixes: b5996f11ea54 ("net: add Hisilicon Network Subsystem basic ethernet support") Signed-off-by: Yonglong Liu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/hisilicon/hns/hns_enet.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c @@ -569,7 +569,6 @@ static int hns_nic_poll_rx_skb(struct hn skb = *out_skb = napi_alloc_skb(&ring_data->napi, HNS_RX_HEAD_SIZE); if (unlikely(!skb)) { - netdev_err(ndev, "alloc rx skb fail\n"); ring->stats.sw_err_cnt++; return -ENOMEM; } @@ -1060,7 +1059,6 @@ static int hns_nic_common_poll(struct na container_of(napi, struct hns_nic_ring_data, napi); struct hnae_ring *ring = ring_data->ring; -try_again: clean_complete += ring_data->poll_one( ring_data, budget - clean_complete, ring_data->ex_process); @@ -1070,7 +1068,7 @@ try_again: napi_complete(napi); ring->q->handle->dev->ops->toggle_ring_irq(ring, 0); } else { - goto try_again; + return budget; } }