Re: scsi_lib: fix scsi_io_completion's SG_IO error propagation

[Mike Snitzer <snitzer@redhat.com>]

Hi James,

Seems this one slipped through the cracks.  Please review/apply.

Thanks,
Mike

On Thu, May 31 2012 at  4:33pm -0400,
Moger, Babu <Babu.Moger@netapp.com> wrote:

> Thanks Mike. Looks good.
> 
> > -----Original Message-----
> > From: Mike Snitzer [mailto:snitzer@redhat.com]
> > Sent: Thursday, May 31, 2012 3:24 PM
> > To: Paolo Bonzini
> > Cc: linux-scsi@vger.kernel.org; Moger, Babu; hare@suse.de;
> > michaelc@cs.wisc.edu; James.Bottomley@hansenpartnership.com;
> > stable@vger.kernel.org.#.3.4
> > Subject: Re: scsi_lib: fix scsi_io_completion's SG_IO error propagation
> > 
> > On Thu, May 31 2012 at  3:51pm -0400,
> > Paolo Bonzini <pbonzini@redhat.com> wrote:
> > 
> > > Il 31/05/2012 21:05, Mike Snitzer ha scritto:
> > > > The following v3.4-rc1 commit unmasked an existing bug in
> > > > scsi_io_completion's SG_IO error handling:
> > > > 47ac56d [SCSI] scsi_error: classify some ILLEGAL_REQUEST sense as a
> > permanent TARGET_ERROR
> > > >
> > > > Given that certain ILLEGAL_REQUEST are now properly categorized as
> > > > TARGET_ERROR the host_byte is being set (before host_byte wasn't ever
> > > > set for these ILLEGAL_REQUEST).
> > > >
> > > > In scsi_io_completion, initialize req->errors with cmd->result _after_
> > > > the SG_IO block that calls __scsi_error_from_host_byte (which may
> > > > modify the host_byte).
> > > >
> > > > Before this fix:
> > > >
> > > >     cdb to send: 12 01 01 00 00 00
> > > > ioctl(3, SG_IO, {'S', SG_DXFER_NONE, cmd[6]=[12, 01, 01, 00, 00, 00],
> > > >     mx_sb_len=32, iovec_count=0, dxfer_len=0, timeout=20000, flags=0,
> > > >     status=02, masked_status=01, sb[19]=[70, 00, 05, 00, 00, 00, 00, 0b,
> > > >     00, 00, 00, 00, 24, 00, 00, 00, 00, 00, 00], host_status=0x10,
> > > >     driver_status=0x8, resid=0, duration=0, info=0x1}) = 0
> > > > SCSI Status: Check Condition
> > > >
> > > > Sense Information:
> > > > sense buffer empty
> > > >
> > > > After:
> > > >
> > > >     cdb to send: 12 01 01 00 00 00
> > > > ioctl(3, SG_IO, {'S', SG_DXFER_NONE, cmd[6]=[12, 01, 01, 00, 00, 00],
> > > >     mx_sb_len=32, iovec_count=0, dxfer_len=0, timeout=20000, flags=0,
> > > >     status=02, masked_status=01, sb[19]=[70, 00, 05, 00, 00, 00, 00, 0b,
> > > >     00, 00, 00, 00, 24, 00, 00, 00, 00, 00, 00], host_status=0,
> > > >     driver_status=0x8, resid=0, duration=0, info=0x1}) = 0
> > > > SCSI Status: Check Condition
> > > >
> > > > Sense Information:
> > > >  Fixed format, current;  Sense key: Illegal Request
> > > >  Additional sense: Invalid field in cdb
> > > >  Raw sense data (in hex):
> > > >         70 00 05 00 00 00 00 0b  00 00 00 00 24 00 00 00
> > > >         00 00 00
> > > >
> > > > Signed-off-by: Mike Snitzer <snitzer@redhat.com>
> > > > Reviewed-by: Babu Moger <babu.moger@netapp.com>
> > >
> > > Reported-by: Paolo Bonzini <pbonzini@redhat.com>
> > > Tested-by: Paolo Bonzini <pbonzini@redhat.com>
> > 
> > Yes, thanks for backfilling the Reported-by and Tested-by Paolo!