From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Freeing alive fib_info caused by ebc0ffae5
Date: Thu, 04 Nov 2010 11:30:26 +0100
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Le jeudi 04 novembre 2010 =C3=A0 21:23 +1100, Michael Ellerman a =C3=A9=
crit :
> Hi all,
>=20
> I'm running Linus' latest or thereabouts (ff8b16d), and I'm seeing
> "Freeing alive fib_info" messages, from free_fib_info().
>=20
> Actually I only get one per boot, when network interfaces come up.
> Seemingly related I am getting refcount problems when I shutdown, ie.
> unregister_netdevice() sees a usage count of 1, which never decrement=
s.
>=20
> Bisect says it's ebc0ffae5 which causes the problem, or makes it appe=
ar.
>=20
>     fib: RCU conversion of fib_lookup()
>    =20
>     fib_lookup() converted to be called in RCU protected context, no
>     reference taken and released on a contended cache line (fib_clntr=
ef)
>    =20
>=20
> Is this a bug in that commit, or a driver bug exposed?

Hi Michael, thanks for the report (and painful bisection I guess)

Thats hard to say... Is it reproductable on my machine ?

Thanks