Re: [PATCH][RFC/v1][9/12] Add InfiniBand userspace MAD support

From: Greg KH
Date: Tue Nov 23 2004 - 02:50:13 EST


On Mon, Nov 22, 2004 at 03:05:40PM -0800, Roland Dreier wrote:
> Greg> You are letting any user, with any privilege register or
> Greg> unregister an "agent"?
>
> They have to be able to open the device node. We could add a check
> that they have it open for writing but there's not really much point
> in opening this device read-only.

Ok, I remember this conversation a while ago. We discussed this same
thing a number of months back on the openib mailing list. Nevermind :)

> Greg> Also, these "agents" seem to be a type of filter, right? Is
> Greg> there no other way to implement this than an ioctl?
>
> ioctl seems to be the least bad way to me. This really feels like a
> legitimate use of ioctl to me -- we use read/write to handle passing
> data through our file descriptor, and ioctl for control of the
> properties of the descriptor.
>
> What would you suggest as an ioctl replacement?

I really can't think of anything else. It just will require a _lot_ of
vigilant attention to prevent people from adding other ioctls to this
one, right?

Do you have other ioctls planned for this same interface for stage 2 and
future stages of ib implementation for Linux?

thanks,

greg k-h
-
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/