Re: Debugging scsi abort handling ?

Martin Peschke
2014-08-28T12:31:50Z

On Thu, 2014-08-28 at 14:04 +0200, Hannes Reinecke wrote:
> On 08/25/2014 01:15 PM, Paolo Bonzini wrote:
> > - abort the command, and then the driver should never call the
> > ->scsi_done callback for the Scsi_Cmnd*.
> >
> In practice we rely on the latter behaviour; when ->scsi_done is
> called while the command is under eh_abort _really bad things_
> will happen.
> As soon as eh_abort is called control is transferred back to the
> SCSI midlayer, so any LLDD should never send completions for these
> commands back to the midlayer.

Mmh, then there is a small race window starting at the point in time
when the abort function of an LLDD is called up to the point in time
when that abort function has taken the necessary measures to make sure
that scsi_done won't be called for a racing command completion , isn't
it?

Cheers
Martin

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