From patchwork Tue Dec 1 08:53:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 335844 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 831CEC83014 for ; Tue, 1 Dec 2020 09:12:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2512A221FF for ; Tue, 1 Dec 2020 09:12:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bth9T5Jg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389947AbgLAJMU (ORCPT ); Tue, 1 Dec 2020 04:12:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:50514 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388872AbgLAJMU (ORCPT ); Tue, 1 Dec 2020 04:12:20 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 CBACC2067D; Tue, 1 Dec 2020 09:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1606813899; bh=GiIcpuIEXT7xJ0orfc9XiiPQIwDzxmqy4Ut5oxb2zXU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bth9T5JgigG9VVF2vTMD3MPNFOo6MJXwY0DQo7Q7sL/KEynBLtIsg67hsdikob2Dm Yiui1//rb6RafThs2uRSQHdXZIMhDNu7Bmjs/4LS7yY5Eq37r0jfmzFyUanlNdbRk5 xg7ngDGa1cQKK+C/hMPcjfUO3XR+CuSxkTPjxSRU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julian Wiedmann , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.9 097/152] s390/qeth: fix tear down of async TX buffers Date: Tue, 1 Dec 2020 09:53:32 +0100 Message-Id: <20201201084724.571225847@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201201084711.707195422@linuxfoundation.org> References: <20201201084711.707195422@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Julian Wiedmann [ Upstream commit 7ed10e16e50daf74460f54bc922e27c6863c8d61 ] When qeth_iqd_tx_complete() detects that a TX buffer requires additional async completion via QAOB, it might fail to replace the queue entry's metadata (and ends up triggering recovery). Assume now that the device gets torn down, overruling the recovery. If the QAOB notification then arrives before the tear down has sufficiently progressed, the buffer state is changed to QETH_QDIO_BUF_HANDLED_DELAYED by qeth_qdio_handle_aob(). The tear down code calls qeth_drain_output_queue(), where qeth_cleanup_handled_pending() will then attempt to replace such a buffer _again_. If it succeeds this time, the buffer ends up dangling in its replacement's ->next_pending list ... where it will never be freed, since there's no further call to qeth_cleanup_handled_pending(). But the second attempt isn't actually needed, we can simply leave the buffer on the queue and re-use it after a potential recovery has completed. The qeth_clear_output_buffer() in qeth_drain_output_queue() will ensure that it's in a clean state again. Fixes: 72861ae792c2 ("qeth: recovery through asynchronous delivery") Signed-off-by: Julian Wiedmann Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/s390/net/qeth_core_main.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c index 54a7eefe73d19..e3666232a19a8 100644 --- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -501,12 +501,6 @@ static void qeth_cleanup_handled_pending(struct qeth_qdio_out_q *q, int bidx, } } - if (forced_cleanup && (atomic_read(&(q->bufs[bidx]->state)) == - QETH_QDIO_BUF_HANDLED_DELAYED)) { - /* for recovery situations */ - qeth_init_qdio_out_buf(q, bidx); - QETH_CARD_TEXT(q->card, 2, "clprecov"); - } }