On Tue, Apr 25, 2017 at 01:32:59PM +0300, Or Gerlitz wrote:
> On Tue, Apr 25, 2017 at 12:55 PM, Honggang LI <ho...@redhat.com> wrote:
> > From: Honggang Li <ho...@redhat.com>
> >
> > Minimal hard_header_len set by bond_compute_features is ETH_HLEN, which
> > is smaller than IPOIB_HARD_LEN. ipoib_hard_header should check the
> > size of headroom to avoid skb_under_panic.
>
> sounds terrible, ipoib bonding is supported since ~2007, thanks for
> reporting on that.
>
> > [ 122.871493] ipoib_hard_header: skb->head= ffff8808179d9400, skb->data=
> > ffff8808179d9420, skb_headroom= 0x20
> > [ 123.055400] bond0: Releasing backup interface mthca_ib1
> > [ 123.560529] bond_compute_features:1112 bond0 bond_dev->hard_header_len =
> > 14
> > [ 123.568822] CPU: 0 PID: 12336 Comm: ifdown-ib Not tainted 4.9.0-debug #1
>
> did you generate this trace by calling dump_stack or this is existing
> kernel code.
I inserted dump_stack to print this stack for debug.
>
> > Fixes: fc791b633515 ('IB/ipoib: move back IB LL address into the hard
> > header')
>
> this is more of WA to avoid some crash or failure but not fixing the
> actual problem
>
> Erez, can you comment?
>
> Or.
