Re: [PATCH] scsi: libiscsi: Set expecting_cc_ua flag when stop_conn

[Mike Christie]

On 10/12/24 2:55 AM, 张翔 wrote:
> 
> 
>     For commands coming from sd, then scsi_io_completion will end up calling
>     scsi_io_completion_action and seeing the UNIT_ATTENTION and will retry.
>     I'm not saying we shouldn't do a fix like you did below. Just want to
>     make sure I understand the case you describe above.
> 
>  
> For commands coming from sd, then scsi_complete calling scsi_decide_disposition to get "enum scsi_disposition", scsi_decide_disposition seeing the SAM_STAT_CHECK_CONDITION and calling scsi_check_sense function, then scsi_check_sense seeing UNIT_ATTENTION. If expecting_cc_ua == 1, scsi_check_sense return NEEDS_RETRY and scsi_complete will retry.


For sd, scsi_decide_disposition will return SUCCESS. scsi_complete will call
scsi_finish_command. In there we call the upper layer done callback, sd_done,
and it will return 0 as there are no good bytes. scsi_io_completion will
initially complete 0 bytes. If there are retries left then we call
scsi_io_completion_action which sees the UA and will retry.