Re: [PATCH] scsi: libsas: Fix disk not being scanned in after being removed

[Jason Yan <yanaijie@huawei.com>]

On 2024/2/29 2:13, John Garry wrote:
> On 21/02/2024 07:31, Xingui Yang wrote:
>> As of commit d8649fc1c5e4 ("scsi: libsas: Do discovery on empty PHY to
>> update PHY info"), do discovery will send a new SMP_DISCOVER and update
>> phy->phy_change_count. We found that if the disk is reconnected and phy
>> change_count changes at this time, the disk scanning process will not be
>> triggered.
>>
>> So update the PHY info with the last query results.
>>
>> Fixes: d8649fc1c5e4 ("scsi: libsas: Do discovery on empty PHY to 
>> update PHY info")
>> Signed-off-by: Xingui Yang <yangxingui@huawei.com>
>> ---
>>   drivers/scsi/libsas/sas_expander.c | 9 ++++-----
>>   1 file changed, 4 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/scsi/libsas/sas_expander.c 
>> b/drivers/scsi/libsas/sas_expander.c
>> index a2204674b680..9563f5589948 100644
>> --- a/drivers/scsi/libsas/sas_expander.c
>> +++ b/drivers/scsi/libsas/sas_expander.c
>> @@ -1681,6 +1681,10 @@ int sas_get_phy_attached_dev(struct 
>> domain_device *dev, int phy_id,
>>           if (*type == 0)
>>               memset(sas_addr, 0, SAS_ADDR_SIZE);
>>       }
>> +
>> +    if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM))
> 
> It's odd to call sas_set_ex_phy() if we got res == -ECOMM. I mean, in 
> this this case disc_resp is not filled in as the command did not 
> execute, right? I know that is what the current code does, but it is 
> strange.

The current code actually re-send the SMP command and update the PHY 
status only when the the SMP command is responded correctly.

Xinggui, can you please fix this and send v3?

Thanks,
Jason