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Date:   Thu, 11 Aug 2022 22:25:48 -0500
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Subject: Re: [PATCH v3] scsi: iscsi: Fix multiple iscsi session unbind event
 sent to userspace
Content-Language: en-US
To:     Wenchao Hao <haowenchao@huawei.com>, Lee Duncan <lduncan@suse.com>,
        Chris Leech <cleech@redhat.com>,
        "James E . J . Bottomley" <jejb@linux.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        open-iscsi@googlegroups.com, linux-scsi@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     linfeilong@huawei.com
References: <20220802034729.2566787-1-haowenchao@huawei.com>
From:   Mike Christie <michael.christie@oracle.com>
In-Reply-To: <20220802034729.2566787-1-haowenchao@huawei.com>
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On 8/1/22 10:47 PM, Wenchao Hao wrote:
> I found an issue that kernel would send ISCSI_KEVENT_UNBIND_SESSION
> for multiple times which should be fixed.
> 
> This patch introduce target_state in iscsi_cls_session to make
> sure session would send only one ISCSI_KEVENT_UNBIND_SESSION.
> 
> But this would break issue fixed in commit 13e60d3ba287 ("scsi: iscsi:
> Report unbind session event when the target has been removed"). The issue
> is iscsid died for any reason after it send unbind session to kernel, once
> iscsid restart again, it loss kernel's ISCSI_KEVENT_UNBIND_SESSION event.
> 
> Now kernel think iscsi_cls_session has already sent an
> ISCSI_KEVENT_UNBIND_SESSION event and would not send it any more. Which
> would cause userspace unable to logout. Actually the session is in
> invalid state(it's target_id is INVALID), iscsid should not sync this
> session in it's restart.
> 
> So we need to check session's target state during iscsid restart,
> if session is in unbound state, do not sync this session and perform
> session teardown. It's reasonable because once a session is unbound, we
> can not recover it any more(mainly because it's target id is INVALID)
> 

I think we are ok now. Do you have a link to the userspace parts so
I can make sure we have everything covered now?