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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46A40C433F5 for ; Mon, 15 Nov 2021 23:27:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2CBD36325A for ; Mon, 15 Nov 2021 23:27:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350111AbhKOXaQ (ORCPT ); Mon, 15 Nov 2021 18:30:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:44624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245195AbhKOTTs (ORCPT ); Mon, 15 Nov 2021 14:19:48 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2DA1E63513; Mon, 15 Nov 2021 18:30:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637001004; bh=02EdHIL6Z5pYAU9ue9d194kpmRsiT4o2WXsRo9XO3LY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kv+iwFbJo5HxjxgbarIVkoKTcvSLnWKiCc5IQTlUQK4eMfOSgEMaLigyPmjNy93TU 814Dayw29eW8gR7B7vsOz7IW3vq1NyCvpSBfUHzjlVKrHe6+rhzYpIpBZziBYBaDEL IxW//mmCp3APXGILwUy4CdmNoMq2cbzQ8AxeXMYw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Ewan D. Milne" , "Martin K. Petersen" Subject: [PATCH 5.15 009/917] scsi: core: Avoid leaving shost->last_reset with stale value if EH does not run Date: Mon, 15 Nov 2021 17:51:44 +0100 Message-Id: <20211115165429.043239136@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@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: Ewan D. Milne commit 5ae17501bc62a49b0b193dcce003f16375f16654 upstream. The changes to issue the abort from the scmd->abort_work instead of the EH thread introduced a problem if eh_deadline is used. If aborting the command(s) is successful, and there are never any scmds added to the shost->eh_cmd_q, there is no code path which will reset the ->last_reset value back to zero. The effect of this is that after a successful abort with no EH thread activity, a subsequent timeout, perhaps a long time later, might immediately be considered past a user-set eh_deadline time, and the host will be reset with no attempt at recovery. Fix this by resetting ->last_reset back to zero in scmd_eh_abort_handler() if it is determined that the EH thread will not run to do this. Thanks to Gopinath Marappan for investigating this problem. Link: https://lore.kernel.org/r/20211029194311.17504-2-emilne@redhat.com Fixes: e494f6a72839 ("[SCSI] improved eh timeout handler") Cc: stable@vger.kernel.org Signed-off-by: Ewan D. Milne Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/hosts.c | 1 + drivers/scsi/scsi_error.c | 25 +++++++++++++++++++++++++ drivers/scsi/scsi_lib.c | 1 + include/scsi/scsi_cmnd.h | 2 +- include/scsi/scsi_host.h | 1 + 5 files changed, 29 insertions(+), 1 deletion(-) --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -388,6 +388,7 @@ struct Scsi_Host *scsi_host_alloc(struct shost->shost_state = SHOST_CREATED; INIT_LIST_HEAD(&shost->__devices); INIT_LIST_HEAD(&shost->__targets); + INIT_LIST_HEAD(&shost->eh_abort_list); INIT_LIST_HEAD(&shost->eh_cmd_q); INIT_LIST_HEAD(&shost->starved_list); init_waitqueue_head(&shost->host_wait); --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -135,6 +135,23 @@ static bool scsi_eh_should_retry_cmd(str return true; } +static void scsi_eh_complete_abort(struct scsi_cmnd *scmd, struct Scsi_Host *shost) +{ + unsigned long flags; + + spin_lock_irqsave(shost->host_lock, flags); + list_del_init(&scmd->eh_entry); + /* + * If the abort succeeds, and there is no further + * EH action, clear the ->last_reset time. + */ + if (list_empty(&shost->eh_abort_list) && + list_empty(&shost->eh_cmd_q)) + if (shost->eh_deadline != -1) + shost->last_reset = 0; + spin_unlock_irqrestore(shost->host_lock, flags); +} + /** * scmd_eh_abort_handler - Handle command aborts * @work: command to be aborted. @@ -152,6 +169,7 @@ scmd_eh_abort_handler(struct work_struct container_of(work, struct scsi_cmnd, abort_work.work); struct scsi_device *sdev = scmd->device; enum scsi_disposition rtn; + unsigned long flags; if (scsi_host_eh_past_deadline(sdev->host)) { SCSI_LOG_ERROR_RECOVERY(3, @@ -175,12 +193,14 @@ scmd_eh_abort_handler(struct work_struct SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_WARNING, scmd, "retry aborted command\n")); + scsi_eh_complete_abort(scmd, sdev->host); scsi_queue_insert(scmd, SCSI_MLQUEUE_EH_RETRY); return; } else { SCSI_LOG_ERROR_RECOVERY(3, scmd_printk(KERN_WARNING, scmd, "finish aborted command\n")); + scsi_eh_complete_abort(scmd, sdev->host); scsi_finish_command(scmd); return; } @@ -193,6 +213,9 @@ scmd_eh_abort_handler(struct work_struct } } + spin_lock_irqsave(sdev->host->host_lock, flags); + list_del_init(&scmd->eh_entry); + spin_unlock_irqrestore(sdev->host->host_lock, flags); scsi_eh_scmd_add(scmd); } @@ -223,6 +246,8 @@ scsi_abort_command(struct scsi_cmnd *scm spin_lock_irqsave(shost->host_lock, flags); if (shost->eh_deadline != -1 && !shost->last_reset) shost->last_reset = jiffies; + BUG_ON(!list_empty(&scmd->eh_entry)); + list_add_tail(&scmd->eh_entry, &shost->eh_abort_list); spin_unlock_irqrestore(shost->host_lock, flags); scmd->eh_eflags |= SCSI_EH_ABORT_SCHEDULED; --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1143,6 +1143,7 @@ void scsi_init_command(struct scsi_devic cmd->sense_buffer = buf; cmd->prot_sdb = prot; cmd->flags = flags; + INIT_LIST_HEAD(&cmd->eh_entry); INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); cmd->jiffies_at_alloc = jiffies_at_alloc; cmd->retries = retries; --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -68,7 +68,7 @@ struct scsi_pointer { struct scsi_cmnd { struct scsi_request req; struct scsi_device *device; - struct list_head eh_entry; /* entry for the host eh_cmd_q */ + struct list_head eh_entry; /* entry for the host eh_abort_list/eh_cmd_q */ struct delayed_work abort_work; struct rcu_head rcu; --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -556,6 +556,7 @@ struct Scsi_Host { struct mutex scan_mutex;/* serialize scanning activity */ + struct list_head eh_abort_list; struct list_head eh_cmd_q; struct task_struct * ehandler; /* Error recovery thread. */ struct completion * eh_action; /* Wait for specific actions on the