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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_RED,USER_AGENT_GIT autolearn=unavailable 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 BD18FC433B4 for ; Mon, 26 Apr 2021 07:42:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94CF661004 for ; Mon, 26 Apr 2021 07:42:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232621AbhDZHnZ (ORCPT ); Mon, 26 Apr 2021 03:43:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:46814 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232377AbhDZHhc (ORCPT ); Mon, 26 Apr 2021 03:37:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C28D6611C1; Mon, 26 Apr 2021 07:35:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619422540; bh=N0qrNNmDrvxPiMqZ1gkFjGfWlPaqdm4+8Qx63p5iI4U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FhHZoKeIRDnUfnkKMWc7ncrNFFLNG/JvvlCXWHUp9T+adYfuS5nbXJ7fAsQT6jsMh a1pyFYGxY3qjN5MykTH5OS2n7hspLdQtajrVhGTjwkCjEsr3UBse/bJa5RF4Kt52Dc HmAwEW5dxJrMzl/qsdO5aWsa8o+Uy7TMfI8qYo1U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Falcon , Lijun Pan , "David S. Miller" Subject: [PATCH 4.14 31/49] ibmvnic: avoid calling napi_disable() twice Date: Mon, 26 Apr 2021 09:29:27 +0200 Message-Id: <20210426072820.781470176@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210426072819.721586742@linuxfoundation.org> References: <20210426072819.721586742@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: linux-kernel@vger.kernel.org From: Lijun Pan commit 0775ebc4cf8554bdcd2c212669a0868ab68df5c0 upstream. __ibmvnic_open calls napi_disable without checking whether NAPI polling has already been disabled or not. This could cause napi_disable being called twice, which could generate deadlock. For example, the first napi_disable will spin until NAPI_STATE_SCHED is cleared by napi_complete_done, then set it again. When napi_disable is called the second time, it will loop infinitely because no dev->poll will be running to clear NAPI_STATE_SCHED. To prevent above scenario from happening, call ibmvnic_napi_disable() which checks if napi is disabled or not before calling napi_disable. Fixes: bfc32f297337 ("ibmvnic: Move resource initialization to its own routine") Suggested-by: Thomas Falcon Signed-off-by: Lijun Pan Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/ibm/ibmvnic.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -891,8 +891,7 @@ static int __ibmvnic_open(struct net_dev rc = set_link_state(adapter, IBMVNIC_LOGICAL_LNK_UP); if (rc) { - for (i = 0; i < adapter->req_rx_queues; i++) - napi_disable(&adapter->napi[i]); + ibmvnic_napi_disable(adapter); release_resources(adapter); return rc; }