> On Mar 16, 2017, at 3:27 PM, Bart Van Assche <bart.vanassche@xxxxxxxxxxx> wrote:
>
> On Thu, 2017-03-16 at 14:40 -0700, Himanshu Madhani wrote:
>> +static int
>> +scsi_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
>> +
>> +{
>> + struct Scsi_Host *shost = hctx->driver_data;
>> + struct request *req;
>> + struct scsi_cmnd *cmd;
>> +
>> + req = blk_mq_tag_to_rq(shost->tag_set.tags[hctx->queue_num], tag);
>> + if (!req)
>> + return 0;
>> +
>> + cmd = blk_mq_rq_to_pdu(req);
>> + if (!cmd)
>> + return 0;
>> +
>> + if (shost->hostt->poll_queue)
>> + return(shost->hostt->poll_queue(shost, cmd));
>> + else return 0;
>> +}
>
> What will happen if the request with tag 'tag' is completed after the block
> layer decided to call this function and before this function had the chance
> to call blk_mq_tag_to_rq()? Will this trigger a kernel crash? Also, please
> format patches properly. This is what checkpatch reports for this patch:
>
> ERROR: code indent should use tabs where possible
> #244: FILE: drivers/scsi/scsi_lib.c:2161:
> + struct Scsi_Host *shost = hctx->driver_data;$
>
> WARNING: please, no spaces at the start of a line
> #244: FILE: drivers/scsi/scsi_lib.c:2161:
> + struct Scsi_Host *shost = hctx->driver_data;$
>
> ERROR: code indent should use tabs where possible
> #245: FILE: drivers/scsi/scsi_lib.c:2162:
> + struct request *req;$
>
> WARNING: please, no spaces at the start of a line
> #245: FILE: drivers/scsi/scsi_lib.c:2162:
> + struct request *req;$
>
> ERROR: code indent should use tabs where possible
> #246: FILE: drivers/scsi/scsi_lib.c:2163:
> + struct scsi_cmnd *cmd;$
>
> WARNING: please, no spaces at the start of a line
> #246: FILE: drivers/scsi/scsi_lib.c:2163:
> + struct scsi_cmnd *cmd;$
>
> ERROR: code indent should use tabs where possible
> #248: FILE: drivers/scsi/scsi_lib.c:2165:
> + req = blk_mq_tag_to_rq(shost->tag_set.tags[hctx->queue_num], tag);$
>
> WARNING: please, no spaces at the start of a line
> #248: FILE: drivers/scsi/scsi_lib.c:2165:
> + req = blk_mq_tag_to_rq(shost->tag_set.tags[hctx->queue_num], tag);$
>
> ERROR: code indent should use tabs where possible
> #249: FILE: drivers/scsi/scsi_lib.c:2166:
> + if (!req)$
>
> WARNING: please, no spaces at the start of a line
> #249: FILE: drivers/scsi/scsi_lib.c:2166:
> + if (!req)$
>
> ERROR: code indent should use tabs where possible
> #250: FILE: drivers/scsi/scsi_lib.c:2167:
> + return 0;$
>
> WARNING: please, no spaces at the start of a line
> #250: FILE: drivers/scsi/scsi_lib.c:2167:
> + return 0;$
>
> ERROR: code indent should use tabs where possible
> #252: FILE: drivers/scsi/scsi_lib.c:2169:
> + cmd = blk_mq_rq_to_pdu(req);$
>
> WARNING: please, no spaces at the start of a line
> #252: FILE: drivers/scsi/scsi_lib.c:2169:
> + cmd = blk_mq_rq_to_pdu(req);$
>
> ERROR: return is not a function, parentheses are not required
> #257: FILE: drivers/scsi/scsi_lib.c:2174:
> + return(shost->hostt->poll_queue(shost, cmd));
>
> ERROR: trailing statements should be on next line
> #258: FILE: drivers/scsi/scsi_lib.c:2175:
> + else return 0;
>
> WARNING: line over 80 characters
> #262: FILE: drivers/scsi/scsi_lib.c:2179:
> +__scsi_init_hctx(struct blk_mq_hw_ctx *hctx, struct Scsi_Host *shost, unsigned int hctx_idx)
>
> WARNING: Unnecessary space before function pointer name
> #306: FILE: include/scsi/scsi_host.h:139:
> + int (* poll_queue)(struct Scsi_Host *, struct scsi_cmnd *);
>
> ERROR: space prohibited after that '*' (ctx:BxW)
> #306: FILE: include/scsi/scsi_host.h:139:
> + int (* poll_queue)(struct Scsi_Host *, struct scsi_cmnd *);
> ^
> Thanks,
>
> Bart.
We’ll take care of Check patch issue in updated RFC.
Thanks,
- Himanshu
