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Date:   Tue, 22 Nov 2022 10:53:11 -0600
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Subject: Re: [PATCH v6] scsi:iscsi: Fix multiple iscsi session unbind event
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To:     Wenchao Hao <haowenchao@huawei.com>, Lee Duncan <lduncan@suse.com>,
        Chris Leech <cleech@redhat.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        "James E . J . Bottomley" <jejb@linux.ibm.com>
Cc:     open-iscsi@googlegroups.com, linux-scsi@vger.kernel.org,
        linux-kernel@vger.kernel.org, linfeilong@huawei.com
References: <20221108014414.3510940-1-haowenchao@huawei.com>
 <ad54a5dc-b18f-e0e6-4391-1214e5729562@oracle.com>
 <89692b2b-90f7-e8e8-fa77-f14dbe996b72@huawei.com>
From:   Mike Christie <michael.christie@oracle.com>
In-Reply-To: <89692b2b-90f7-e8e8-fa77-f14dbe996b72@huawei.com>
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On 11/21/22 8:17 AM, Wenchao Hao wrote:
> And the function looks like following after change:
> 
> static void __iscsi_unbind_session(struct work_struct *work)
> {
> 	struct iscsi_cls_session *session =
> 			container_of(work, struct iscsi_cls_session,
> 				     unbind_work);
> 	struct Scsi_Host *shost = iscsi_session_to_shost(session);
> 	struct iscsi_cls_host *ihost = shost->shost_data;
> 	unsigned long flags;
> 	unsigned int target_id;
> 
> 	ISCSI_DBG_TRANS_SESSION(session, "Unbinding session\n");
> 
> 	/* Prevent new scans and make sure scanning is not in progress */
> 	mutex_lock(&ihost->mutex);
> 	spin_lock_irqsave(&session->lock, flags);
> 	if (session->target_state != ISCSI_SESSION_TARGET_SCANNED) {

What was the reason for not checking for ALLOCATED and freeing the ida
in that case?

> 		spin_unlock_irqrestore(&session->lock, flags);
> 		mutex_unlock(&ihost->mutex);
> 		ISCSI_DBG_TRANS_SESSION(session, "Skipping target unbinding: Session is %s.\n",
> 					iscsi_session_target_state_name[session->target_state]);
> 		return;
> 	}
> 	target_id = session->target_id;
> 	session->target_id = ISCSI_MAX_TARGET;
> 	session->target_state = ISCSI_SESSION_TARGET_UNBINDING;
> 	spin_unlock_irqrestore(&session->lock, flags);
> 	mutex_unlock(&ihost->mutex);
> 
> 	scsi_remove_target(&session->dev);
> 
> 	spin_lock_irqsave(&session->lock, flags);
> 	session->target_state = ISCSI_SESSION_TARGET_UNBOUND;
> 	spin_unlock_irqrestore(&session->lock, flags);
> 
> 	if (session->ida_used)
> 		ida_free(&iscsi_sess_ida, target_id);
> 
> 	iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
> 	ISCSI_DBG_TRANS_SESSION(session, "Completed target removal\n");
> }
> 
> 
>