[dm-devel] Re: [RFC PATCH 2/4] convert dm to blkerr error values

[Mike Christie]

goggin, edward wrote:
> Mike,
> 
> Can't dec_pending now see different error values for the
> possibly multiple bio clones of a single original bio?

Yep.

> How should it decide which error gets propagated up to
> the original bio?

Have no idea really. We have this problem if the bio gets partially 
completed with different errors for different parts too. I think this 
can happen in SCSI if the front were to get a medium error.


> 
> Looks like the old code and your new code just take the error
> value from the last completed bio which has an error.  While
> this was probably OK when the only error value was -ENXIO, we
> may now need some logic in dec_pending to decide which error
> value has more significance.
> 

Yeah all of that was on the TODO under my comment:

>>Some temporary crap I will fix is the dec_pending fucntions.