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 71C72C728F5 for ; Thu, 27 Feb 2020 14:23:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4AC692468F for ; Thu, 27 Feb 2020 14:23:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582813412; bh=61mj8+xtBd8k0Zsl/yCNkWD7oogYeW2mpynYyCmig8I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=swLRWduL3/bJIcBdG7uvn9jtRFlVQDUw8v0f1UE+NQ2vwjTFqzHNRXYBa67CFJ2qL xdsZCwYR1gg62y7JbB6JHbt+gdE4gej+lBWoOiKYPurBiIWGylBounCygtsclSyvgC fo6VdYPU7Ci1muJZh61Probx+lqj/SsYINuuzuUY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389133AbgB0OO3 (ORCPT ); Thu, 27 Feb 2020 09:14:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:53610 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388745AbgB0OOX (ORCPT ); Thu, 27 Feb 2020 09:14:23 -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 CC5BE2469F; Thu, 27 Feb 2020 14:14:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582812862; bh=61mj8+xtBd8k0Zsl/yCNkWD7oogYeW2mpynYyCmig8I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xe1nT9879Cvce7IG9pvK70V0FBELGq0Rxyt5BZSXGJc9JBBOfM1FpcVGmPqlkLJ8M U5PwJnXzdfdSf9gydmssTFKP0bOYK9hIgkOPBjOkdrm6+a8tpARsP0iK8GDRZLspbe 7NvFYUBD8xrU2Zp1X8Na/0zv/JLCnQ6E3syxZmxs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Zakharov , Mike Christie , Bart Van Assche , "Martin K. Petersen" Subject: [PATCH 5.5 044/150] scsi: Revert "target/core: Inline transport_lun_remove_cmd()" Date: Thu, 27 Feb 2020 14:36:21 +0100 Message-Id: <20200227132239.457970632@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200227132232.815448360@linuxfoundation.org> References: <20200227132232.815448360@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: Bart Van Assche commit c14335ebb92a98646ddbf447e6cacc66de5269ad upstream. Commit 83f85b8ec305 postponed the percpu_ref_put(&se_cmd->se_lun->lun_ref) call from command completion to the time when the final command reference is dropped. That approach is not compatible with the iSCSI target driver because the iSCSI target driver keeps the command with the highest stat_sn after it has completed until the next command is received (see also iscsit_ack_from_expstatsn()). Fix this regression by reverting commit 83f85b8ec305. Fixes: 83f85b8ec305 ("scsi: target/core: Inline transport_lun_remove_cmd()") Cc: Pavel Zakharov Cc: Mike Christie Cc: Link: https://lore.kernel.org/r/20200210051202.12934-1-bvanassche@acm.org Reported-by: Pavel Zakharov Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/target/target_core_transport.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -666,6 +666,11 @@ static int transport_cmd_check_stop_to_f target_remove_from_state_list(cmd); + /* + * Clear struct se_cmd->se_lun before the handoff to FE. + */ + cmd->se_lun = NULL; + spin_lock_irqsave(&cmd->t_state_lock, flags); /* * Determine if frontend context caller is requesting the stopping of @@ -693,6 +698,17 @@ static int transport_cmd_check_stop_to_f return cmd->se_tfo->check_stop_free(cmd); } +static void transport_lun_remove_cmd(struct se_cmd *cmd) +{ + struct se_lun *lun = cmd->se_lun; + + if (!lun) + return; + + if (cmpxchg(&cmd->lun_ref_active, true, false)) + percpu_ref_put(&lun->lun_ref); +} + static void target_complete_failure_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); @@ -783,6 +799,8 @@ static void target_handle_abort(struct s WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0); + transport_lun_remove_cmd(cmd); + transport_cmd_check_stop_to_fabric(cmd); } @@ -1708,6 +1726,7 @@ static void target_complete_tmr_failure( se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST; se_cmd->se_tfo->queue_tm_rsp(se_cmd); + transport_lun_remove_cmd(se_cmd); transport_cmd_check_stop_to_fabric(se_cmd); } @@ -1898,6 +1917,7 @@ void transport_generic_request_failure(s goto queue_full; check_stop: + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; @@ -2195,6 +2215,7 @@ queue_status: transport_handle_queue_full(cmd, cmd->se_dev, ret, false); return; } + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); } @@ -2289,6 +2310,7 @@ static void target_complete_ok_work(stru if (ret) goto queue_full; + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } @@ -2314,6 +2336,7 @@ static void target_complete_ok_work(stru if (ret) goto queue_full; + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } @@ -2349,6 +2372,7 @@ queue_rsp: if (ret) goto queue_full; + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } @@ -2384,6 +2408,7 @@ queue_status: break; } + transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; @@ -2710,6 +2735,9 @@ int transport_generic_free_cmd(struct se */ if (cmd->state_active) target_remove_from_state_list(cmd); + + if (cmd->se_lun) + transport_lun_remove_cmd(cmd); } if (aborted) cmd->free_compl = &compl; @@ -2781,9 +2809,6 @@ static void target_release_cmd_kref(stru struct completion *abrt_compl = se_cmd->abrt_compl; unsigned long flags; - if (se_cmd->lun_ref_active) - percpu_ref_put(&se_cmd->se_lun->lun_ref); - if (se_sess) { spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); list_del_init(&se_cmd->se_cmd_list);