Re: mptsas driver cannot detect hotplugging disk with the LSI SCSI SAS1068 controller in Ubuntu guest on VMware

[Gavin Guo]

Hi Hannes,

Thank you for looking into the issue. If there is anything I can help
to test the patch? I appreciate your help. Thank you.

On Fri, Oct 6, 2017 at 9:08 AM, Gavin Guo <gavin.guo@xxxxxxxxxxxxx> wrote:
> On Mon, Oct 2, 2017 at 10:32 PM, Hannes Reinecke <hare@xxxxxxx> wrote:
>> On 09/27/2017 09:33 AM, Gavin Guo wrote:
>>> There is a problem in the latest upstream kernel with the device:
>>>
>>> $ grep -i lsi lspci
>>> 03:00.0 Serial Attached SCSI controller [0107]: LSI Logic / Symbios
>>> Logic SAS1068 PCI-X Fusion-MPT SAS [1000:0054] (rev 01)
>>>
>>> The device is simulated by the VMware ESXi 5.5
>>>
>>> When hotplugging a new disk to the Guest Ubuntu OS, the latest kernel
>>> cannot automatically probe the disk. However, on the v3.19.0-80.88
>>> kernel, the disk can be dynamically probed and show the following
>>> info message:
>>>
>>> mptsas: ioc0: attaching ssp device: fw_channel 0, fw_id 1, phy 1,
>>> sas_addr 0x5000c29a6bdae0f5
>>> scsi 2:0:1:0: Direct-Access     VMware   Virtual disk     1.0  PQ: 0
>>> ANSI: 2
>>> sd 2:0:1:0: Attached scsi generic sg2 type 0
>>> sd 2:0:1:0: [sdb] 2097152 512-byte logical blocks: (1.07 GB/1.00 GiB)
>>> sd 2:0:1:0: [sdb] Write Protect is off
>>> sd 2:0:1:0: [sdb] Mode Sense: 61 00 00 00
>>> sd 2:0:1:0: [sdb] Cache data unavailable
>>> sd 2:0:1:0: [sdb] Assuming drive cache: write through
>>>  sdb: unknown partition table
>>> sd 2:0:1:0: [sdb] Attached SCSI disk
>>>
>>> After looking up the message:
>>> mptsas: ioc0: attaching ssp device: fw_channel 0, fw_id 1, phy 1,
>>> sas_addr 0x5000c29a6bdae0f5
>>>
>>> I found it comes from the path:
>>> mptsas_firmware_event_work -> mptsas_send_sas_event ->
>>> mptsas_hotplug_work -> mptsas_add_end_device
>>>
>>> I'll appreciate if anyone can give the idea: If it's possible that the
>>> irq from the simulated LSI SAS controller didn't come in to trigger
>>> the event? However, it can work on the v3.19 kernel so if there is
>>> any driver implementation issue in the latest kernel.
>>>
>> This is an issue with the mptsas driver, who originally assumed that no
>> system will have direct-attached SAS devices.
>> VMWare chose to implement exactly that, so the hotplug detection logic
>> is flawed here.
>> I'll be sending a patch.
>>
>> Cheers,
>>
>> Hannes
>> --
>> Dr. Hannes Reinecke                Teamlead Storage & Networking
>> hare@xxxxxxx                                   +49 911 74053 688
>> SUSE LINUX GmbH, Maxfeldstr. 5, 90409 NÃrnberg
>> GF: F. ImendÃrffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
>> HRB 21284 (AG NÃrnberg)
>
> Thank you in advance. Please add me to the CC list when you send out
> the patch and I can help to verify that.