Re: detaching ethernet interfaces..
Re: detaching ethernet interfaces..
- Subject: Re: detaching ethernet interfaces..
- From: "Justin C. Walker" <email@hidden>
- Date: Fri, 25 Jan 2002 13:30:06 -0800
On Friday, January 25, 2002, at 12:53 PM, Andrew Gallatin wrote:
Is it possible to detach an ethernet interface in 10.1 / Darwin 1.4
after it has been ifconfig'ed up? (and down again)
Eg, looking at the source code for ether_attach_inet, I see:
/* XXX avoid free'ing the interface */
ifp->if_eflags |= IFEF_DETACH_DISABLED;
I don't see IFEF_DETACH_DISABLED being cleared anywhere. So it looks
as though an interface becomes unloadable once its been configured.
Is this true? Why??
You mean "un-unloadable", right?
It is true. Currently, while you can unload drivers in general, Darwin
doesn't have the necessary mechanisms to run down all the stashed copies
of the pointer to the driver's 'ifnet' structure. Therefore, if we did
allow unloading, it would likely to come back to haunt us (in the form
of a DSI, or other nasty surprise, when referencing a location that's no
longer valid in kernel memory).
Regards,
Justin
--
Justin C. Walker, Curmudgeon-At-Large *
Institute for General Semantics | If you're not confused,
| You're not paying attention
*--------------------------------------*-------------------------------*