Hannes Reinecke <h...@suse.de> writes:

> On 10/08/2015 06:54 PM, Vitaly Kuznetsov wrote:
>> Some host adapters (e.g. Hyper-V storvsc) are known for not respecting the
>> SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall contain at
>> least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1: scsi scan:
>> INQUIRY result too short (5), using 36' messages on console. This can be
>> problematic for slow consoles. Introduce short_inquiry flag in struct
>> Scsi_Host to print the message once per host.
>> 
>> Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
>> ---
>> Changes since v2:
>> - This is a successor of previously sent (and still not merged) "scsi:
>>   introduce short_inquiry flag for broken host adapters" patch. I'm not
>>   particularly sure which solution is better but I'm leaning towards this
>>   one as it doesn't require changes to adapter drivers.
>> ---
>>  drivers/scsi/scsi_scan.c | 9 ++++++---
>>  include/scsi/scsi_host.h | 3 +++
>>  2 files changed, 9 insertions(+), 3 deletions(-)
>> 
>> diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
>> index f9f3f82..cd347e4 100644
>> --- a/drivers/scsi/scsi_scan.c
>> +++ b/drivers/scsi/scsi_scan.c
>> @@ -701,9 +701,12 @@ static int scsi_probe_lun(struct scsi_device *sdev, 
>> unsigned char *inq_result,
>>       * strings.
>>       */
>>      if (sdev->inquiry_len < 36) {
>> -            sdev_printk(KERN_INFO, sdev,
>> -                        "scsi scan: INQUIRY result too short (%d),"
>> -                        " using 36\n", sdev->inquiry_len);
>> +            if (!sdev->host->short_inquiry) {
>> +                    shost_printk(KERN_INFO, sdev->host,
>> +                                "scsi scan: INQUIRY result too short (%d),"
>> +                                " using 36\n", sdev->inquiry_len);
>> +                    sdev->host->short_inquiry = 1;
>> +            }
>>              sdev->inquiry_len = 36;
>>      }
>>  
> At least you need to check if you've received any valid data here;
> 'INQUIRY result too short' is also a common error if the interrupt
> is hosed when trying to access the device.
> So please check for 'inquiry_len > 4' before setting 'short_inquiry'.

Currently we proceed even with a shorter reply... Should we abort the
scan (and return -EOI?) in case we got inquiry_len <= 4?

Thanks,

-- 
  Vitaly
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to