From patchwork Mon Feb 8 15:00:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 379276 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=-19.3 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_BLOCKED, 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 ACF30C433E6 for ; Mon, 8 Feb 2021 15:05:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 687AC64EE5 for ; Mon, 8 Feb 2021 15:05:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232315AbhBHPE4 (ORCPT ); Mon, 8 Feb 2021 10:04:56 -0500 Received: from mail.kernel.org ([198.145.29.99]:52238 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231782AbhBHPDo (ORCPT ); Mon, 8 Feb 2021 10:03:44 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3845464EB1; Mon, 8 Feb 2021 15:02:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1612796552; bh=zvZu11juC4Hap7y//fmhDTOkV3LesKGV9s3ZOA+39GQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WYtK0PdCo69bexfgbO9MNit5dxUfg+7Hx/8sVA3guC4reom/lC08EoDrfyrcC2iuO EP+Bq02739s0/9lT3OROMEcP41CXiNPfWU6COvkrwsypWp3EZcTRaKrIOJAT3oDFbO 4nD2UWYl/JE/Gv2BaMW+pbK/i4czefRGlDpJt4XA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Javed Hasan , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.4 13/38] scsi: libfc: Avoid invoking response handler twice if ep is already completed Date: Mon, 8 Feb 2021 16:00:35 +0100 Message-Id: <20210208145805.821547745@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210208145805.279815326@linuxfoundation.org> References: <20210208145805.279815326@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Javed Hasan [ Upstream commit b2b0f16fa65e910a3ec8771206bb49ee87a54ac5 ] A race condition exists between the response handler getting called because of exchange_mgr_reset() (which clears out all the active XIDs) and the response we get via an interrupt. Sequence of events: rport ba0200: Port timeout, state PLOGI rport ba0200: Port entered PLOGI state from PLOGI state xid 1052: Exchange timer armed : 20000 msecs  xid timer armed here rport ba0200: Received LOGO request while in state PLOGI rport ba0200: Delete port rport ba0200: work event 3 rport ba0200: lld callback ev 3 bnx2fc: rport_event_hdlr: event = 3, port_id = 0xba0200 bnx2fc: ba0200 - rport not created Yet!! /* Here we reset any outstanding exchanges before freeing rport using the exch_mgr_reset() */ xid 1052: Exchange timer canceled /* Here we got two responses for one xid */ xid 1052: invoking resp(), esb 20000000 state 3 xid 1052: invoking resp(), esb 20000000 state 3 xid 1052: fc_rport_plogi_resp() : ep->resp_active 2 xid 1052: fc_rport_plogi_resp() : ep->resp_active 2 Skip the response if the exchange is already completed. Link: https://lore.kernel.org/r/20201215194731.2326-1-jhasan@marvell.com Signed-off-by: Javed Hasan Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/libfc/fc_exch.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c index b20c575564e43..a088f74a157c7 100644 --- a/drivers/scsi/libfc/fc_exch.c +++ b/drivers/scsi/libfc/fc_exch.c @@ -1577,8 +1577,13 @@ static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) rc = fc_exch_done_locked(ep); WARN_ON(fc_seq_exch(sp) != ep); spin_unlock_bh(&ep->ex_lock); - if (!rc) + if (!rc) { fc_exch_delete(ep); + } else { + FC_EXCH_DBG(ep, "ep is completed already," + "hence skip calling the resp\n"); + goto skip_resp; + } } /* @@ -1597,6 +1602,7 @@ static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) if (!fc_invoke_resp(ep, sp, fp)) fc_frame_free(fp); +skip_resp: fc_exch_release(ep); return; rel: @@ -1841,10 +1847,16 @@ static void fc_exch_reset(struct fc_exch *ep) fc_exch_hold(ep); - if (!rc) + if (!rc) { fc_exch_delete(ep); + } else { + FC_EXCH_DBG(ep, "ep is completed already," + "hence skip calling the resp\n"); + goto skip_resp; + } fc_invoke_resp(ep, sp, ERR_PTR(-FC_EX_CLOSED)); +skip_resp: fc_seq_set_resp(sp, NULL, ep->arg); fc_exch_release(ep); }