Re: [Patch 3/4] ipc/mqueue: strengthen checks on mqueue creation

[KOSAKI Motohiro]

(5/1/12 7:02 PM), Doug Ledford wrote:
> On 5/1/2012 4:18 PM, KOSAKI Motohiro wrote:
> > > > But ENOMEM is more inaccurate. It almostly is used for kmalloc failure.
> > >
> > > I chose ENOMEM for that particular error because above there we have
> > > checked the passed in arguments to make sure that they don't violate our
> > > allowances for max message or max message size.  If we violate either of
> > > those items, we return EINVAL.  In this case, neither of the values is
> > > invalid, it's just that together they make an overly large allocation.
> > > I would see that as more helpful to a programmer than EINVAL when the
> > > values are within the maximums allowed.  At least with ENOMEM the
> > > programmer knows they have to reduce their combined message size and
> > > message count in order to get things working.
> >
> > Incorrect. When ENOMEM is returned, programmers can't know
> > which problem was happen 1) kernel has real memory starvation
> > or 2) queue limitation exceed was happen. The problem is, you
> > introduced new overloaded error code for avoiding overload error code.
> > It doesn't make sense. My question was, why can't you choose no
> > overload error code if you want accurate one?
>
> OK, then would EOVERFLOW suit things better?

I have no seen to any confusion source this. thank you.

then, ack all of this series.
 Acked-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>


> All this reminds me that when this is taken into Linus' kernel, we need
> to coordinate a man page update for the mq subsystem.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/