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From:   Wenchao Hao <haowenchao@huawei.com>
Subject: [bug report]scsi: drive letter drift problem
To:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        "Jason Wang" <jasowang@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        "Stefan Hajnoczi" <stefanha@redhat.com>,
        <linux-scsi@vger.kernel.org>,
        <virtualization@lists.linux-foundation.org>,
        <linux-kernel@vger.kernel.org>
CC:     Zhiqiang Liu <liuzhiqiang26@huawei.com>, Wu Bo <wubo40@huawei.com>,
        <linfeilong@huawei.com>, <yuzhanzhan@huawei.com>,
        <haowenchao@huawei.com>
Message-ID: <7ae2293e-71a9-f68e-0bfb-b4a70ecf493e@huawei.com>
Date:   Mon, 12 Jul 2021 12:47:05 +0800
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We deploy two SCSI disk in one SCSI host(virtio-scsi bus) for one 
machine, whose ids are [0:0:0:0] and [0:0:1:0].

Mostly, the device letter are assigned as following after reboot:
[0:0:0:0] --> sda
[0:0:1:0] --> sdb

While in rare cases, the device letter shown as following:
[0:0:0:0] --> sdb
[0:0:1:0] --> sda

Could we guarantee "sda" is assigned to [0:0:0:0] and "sdb" is assigned 
to [0:0:1:0] or not?
If we can, then how?