Re: kldunload if_sk -> LOR & panic

On Sun, 18 Jul 2004, Brian Fundakowski Feldman wrote:

> On Sun, Jul 18, 2004 at 03:11:22PM +0000, Bjoern A. Zeeb wrote:
> > Hi,
> >
> > tried to unload if_sk for testing the newly built module with dwhite's
> > locking patch (will be loaded after reset now :( ).
> > resulted in this on my amd64:
> >
> > --- cut ---
> > noc# kldunload if_sk
> > e1000phy0: detached
> > miibus0: detached
> > lock order reversal
> >  1st 0xffffff0030ac7870 skc0 (network driver) _at_ sys/pci/if_sk.c:2604
> >  2nd 0xffffff0000b91af0 radix node head (radix node head) _at_ sys/netinet/in_rmx.c:391
> > Stack backtrace:
> > witness_checkorder() at witness_checkorder+0x4a6
> > _mtx_lock_flags() at _mtx_lock_flags+0x39
> > in_ifadown() at in_ifadown+0x5b
> > in_control() at in_control+0x81c
> > if_detach() at if_detach+0x50b
> > ether_ifdetach() at ether_ifdetach+0x25
> > sk_detach() at sk_detach+0x6d
> > (null)() at 0
> > null_method() at null_method
>
> At the point where it's actually detaching, once it's detached the methods
> that access its softc, it should drop its softc lock before calling the
> network-level detach routines.

I think this is handled by dwhite's patch so I should be safe now.
Perhaps someone could work towards committing a cleaned up version of
this patch ?

-- 
Bjoern A. Zeeb				bzeeb at Zabbadoz dot NeT