Re: [PATCH] [RFC] sd: make error handling more robust

[Tony Battersby <tonyb@cybernetics.com>]

Salyzyn, Mark wrote:
> Serendipity, been working an issue for the past week where error reporting from aacraid's HARDWARE_ERROR when an array was marked DEAD in the Adapter was not propagating to MD. The trigger for this investigation was "AACRAID driver broken in 2.6.22.x (and beyond?) [WAS: Re: 2.6.22.16 MD raid1 doesn't mark removed disk faulty, MD thread goes UN]" as authored my Mike Snitzer.
>
> I had attacked this yesterday by setting the deferred bit (0xF1) rather than invalidating the sense data (0x70) in the LLD (Patch to the aacraid would be forthcoming following some testing). The Valid bit in the SCSI layer sometimes (too many kernels, I am talking generically) throws away all the content and keys of the sense data, at least deferred appears to report that the info does not accompany the sense data.
>
> The change needs to be SCSI compliant and possibly endure back-porting to other kernels. So where are we going to put this, in each respective LLD (invalidating info, but not the keys), in sd.c (where the bad_lba is calculated) or in scsi_error.c (where the info field is picked up)?
>
> Sincerely -- Mark Salyzyn
>
>   
Have you tried setting VALID=1 and DEFERRED=0 (0xF0), with the sense
information bytes containing the LBA of the first requested sector from
the read/write CDB?  Note that if you support arrays > 2 TB, you may
have to use the newer descriptor sense format to return sector numbers
>= 2^32.

Tony