Re: Kernel 2.6.x hangs with Symbios Logic 53c1010 Ultra3 SCSI Ada pter

[Thomas Babut <thomas@babut.net>]

Matthew Wilcox wrote:
> On Fri, Nov 05, 2004 at 04:25:03PM -0000, SUPPORT wrote:
> 
>>I've been seeing problems with various tape drives and PPR. And a SCSI 3 SE
>>disk is interesting as well! SE and PPR don't get on too well;)
> 
> 
> ... yes ...
> 
> I think we should *never* attempt PPR on a SE bus, even when the drive
> supports it.  We've seen bugs in Seagate drive firmware because of this,
> so let's stop doing it.
> 
> How does this patch (whitespace damaged, apply by hand) make people feel?
> 
> --- linux-2.6/drivers/scsi/sym53c8xx_2/sym_hipd.c       2004-11-02 12:59:53.0000
> 00000 -0700
> +++ sym2-2.6/drivers/scsi/sym53c8xx_2/sym_hipd.c        2004-11-05 13:20:18.0000
> 00000 -0700
> @@ -1455,7 +1455,7 @@
>                 st->options &= ~PPR_OPT_DT;
>         }
>  
> -       if (!(np->features & FE_ULTRA3))
> +       if (np->scsi_mode != SMODE_LVD || !(np->features & FE_ULTRA3))
>                 st->options &= ~PPR_OPT_DT;
>  
>         if (st->options & PPR_OPT_DT) {
> 
> 
> 
>>Matthew - I have attached some bits of SCSI analyser traces which I hope may
>>be useful. An IBM SCSI 3 SE disk and a couple of LTO tape drives - IBM and
>>HP. The HP causes severe problems as modprobe hangs without the fix. I have
>>also seen drives that do unexpected disconnects if they get sent PPR.
> 
> 
> Thanks, those are interesting.  It's good to see that we really are
> spitting PPR out onto the wire when we shouldn't be.
> 
> 
>>I have been toying with the idea of disabling PPR capability if PPR is
>>rejected - forcing sdev->ppr=0 in the driver when it determines PPR has been
>>rejected - but I'm not sure that's right. There are drives which reject
>>negotiation - legacy sync and wide at least - while they are initialising
>>but will then accept it later on.
> 
> 
> I think disabling PPR on an SE bus should be a better fix than that.
> 
> 
>>Question - where does the full source for the sym53c8xx_2 driver live these
>>days now that Gerard no long maintains it?
> 
> 
> My primary development for this driver lives in the parisc-linux CVS.
> I publish patches on an irregular basis.  If this patch fixes a
> significant number of problems (and it seems it might), I'll do a
> 2.1.18n release.
> 

None of the patches you posted solved my problems. I'm loosing hope... ;)

Regards,
Thomas Babut