Hi Bart Thanks for your answer. I looked at SCSI core source codes these days, UFS also follows SCSI core error handling. There is already re-issue behavior, and assign 5 retries for each UFS request if there is error. > >On 02/12/18 04:21, Bean Huo (beanhuo) wrote >> I am looking at UFS error handling, but I didn't notice re-issues >> requests with UTP error to the host controller. According UFS host >> spec, "host software either completes the request that had the error >> and requests still outstanding with error to higher level software, or >> re-issues these requests to the host controller". For the latest Linux >> UFS driver, it belongs to former one? If I am wrong, please correct >> me. > >Hello Bean, > >I'm afraid that reissuing a failed write forever could cause an infinite loop that >makes e.g. user space processes unkillable or that could cause an orderly >system shutdown to hang. I'm not sure that we want such behavior. > >If you want to learn more about how the SCSI core handles failed writes, >please have a look at scsi_decide_disposition(). A possible approach to >modify the error handling behavior is to stack a dm driver on top of the SCSI >core that implements the desired behavior. > >Bart.