Jeff Garzik wrote:
> Brad Campbell wrote:
> 
>> I think I have this timeout error issue pegged now.
>>
>> I know this is both wrong, ugly and likely to cause internal kernel 
>> damage, but for the purpose of pegging what I think may be the culprit 
>> it works around the error nicely here
>>
>> brad@srv:/usr/src$ diff -u 
>> temp/linux-2.6.8.1/drivers/scsi/libata-scsi.c 
>> linux-2.6.8.1/drivers/scsi/libata-scsi.c
>> --- temp/linux-2.6.8.1/drivers/scsi/libata-scsi.c       2004-08-14 
>> 14:55:19.000000000 +0400
>> +++ linux-2.6.8.1/drivers/scsi/libata-scsi.c    2004-08-18 
>> 01:04:11.000000000 +0400
>> @@ -213,6 +213,7 @@
>>
>>         ap = (struct ata_port *) &host->hostdata[0];
>>         ap->ops->eng_timeout(ap);
>> +       host->host_failed--;
>>
>>         DPRINTK("EXIT\n");
>>         return 0;
>>
>> The issue is that the libata installed eh_strategy_handler does not 
>> complete the error as
>> scsi_unjam_host -> scsi_eh_abort_cmds -> scsi_eh_finish_cmd does.
> 
> 
> 
> Well, well, well.  If I had a libata Honorary Hacker merit badge, I 
> would give it to you.
> 
> It is highly likely that your patch is doing the right thing.  Doug 
> Ledford, 2.4.x SCSI maintainer, pointed out to me recently that my 2.4.x 
> error handling code MUST update a couple variables, otherwise error 
> handling would hang as you see.  The reason is that scsi_unjam_host(), 
> on both 2.4.x and 2.6.x, is the only ->eh_strategy_handler until libata 
> came along.
> 
> So, it is likely that there are a few details the scsi_unjam_host() 
> performs, that needs to do too.
> 
> Thanks much for your excellent detective work, I'll see where to best 
> put this change...

Jeff,
It probably doesn't rate any gold stars but while your patching
libata-scsi.c could you slip this fix in as well.

The patch is against lk 2.6.8.1 . The same patch is needed
(give or take fuzz) in lk 2.4.27 .

Changes:
    - send vendor, product and rev strings back for 36 byte
      INQUIRYs
    - set the additional length field to indicate 96 byte
      response is available

Doug Gilbert