On Thursday 12/17 at 17:08 -0800, Eric Dumazet wrote: > On Thu, 2015-12-17 at 15:52 -0800, Calvin Owens wrote: > > With built-in netconsole and IXGBE, configuring netconsole via the kernel > > cmdline results in the following panic at boot: > > > > netpoll: netconsole: device eth0 not up yet, forcing it > > usb 2-1: new high-speed USB device number 2 using ehci-pci > > ixgbe 0000:03:00.0: registered PHC device on eth0 > > BUG: unable to handle kernel NULL pointer dereference at > > 0000000000000810 > > <snip> > > Call Trace: > > [<ffffffff81578661>] ? vxlan_get_rx_port+0x41/0xa0 > > [<ffffffff81586828>] ixgbe_open+0x4e8/0x540 > > [<ffffffff8168045c>] __dev_open+0xac/0x120 > > [<ffffffff81680506>] dev_open+0x36/0x70 > > [<ffffffff8169abec>] netpoll_setup+0x23c/0x300 > > [<ffffffff8169a66a>] ? netpoll_parse_options+0x19a/0x200 > > [<ffffffff81d797a8>] ? option_setup+0x1f/0x1f > > [<ffffffff81d79882>] init_netconsole+0xda/0x262 > > [<ffffffff81d797a8>] ? option_setup+0x1f/0x1f > > [<ffffffff810003a8>] do_one_initcall+0x88/0x1b0 > > [<ffffffff81d31144>] kernel_init_freeable+0x14a/0x1e3 > > [<ffffffff81d308f1>] ? do_early_param+0x8c/0x8c > > [<ffffffff81778610>] ? rest_init+0x80/0x80 > > [<ffffffff8177861e>] kernel_init+0xe/0xe0 > > [<ffffffff8177dc5f>] ret_from_fork+0x3f/0x70 > > [<ffffffff81778610>] ? rest_init+0x80/0x80 > > > > This happens because IXGBE assumes that vxlan has already been initialized. > > The cleanest way to fix this is to just initialize netconsole after all the > > other core networking stuff has completed. > > > > Signed-off-by: Calvin Owens <calvinow...@fb.com> > > --- > > drivers/net/Makefile | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/net/Makefile b/drivers/net/Makefile > > index 900b0c5..31557d0 100644 > > --- a/drivers/net/Makefile > > +++ b/drivers/net/Makefile > > @@ -15,7 +15,6 @@ obj-$(CONFIG_MACVTAP) += macvtap.o > > obj-$(CONFIG_MII) += mii.o > > obj-$(CONFIG_MDIO) += mdio.o > > obj-$(CONFIG_NET) += Space.o loopback.o > > -obj-$(CONFIG_NETCONSOLE) += netconsole.o > > obj-$(CONFIG_PHYLIB) += phy/ > > obj-$(CONFIG_RIONET) += rionet.o > > obj-$(CONFIG_NET_TEAM) += team/ > > @@ -26,6 +25,7 @@ obj-$(CONFIG_VXLAN) += vxlan.o > > obj-$(CONFIG_GENEVE) += geneve.o > > obj-$(CONFIG_NLMON) += nlmon.o > > obj-$(CONFIG_NET_VRF) += vrf.o > > +obj-$(CONFIG_NETCONSOLE) += netconsole.o > > > > # > > # Networking Drivers > > > Looks odd to rely on link order, but we might already rely on this... > > Have you considered using device_initcall() instead of late_initcall() > in vxlan ?
I'll look. As-is though, I think a similar problem would happen if you tried to use a virtio_net device with netconsole= cmdline (although that is admittedly a bizarre use case). The Makefile patch seemed like the best way to ensure this can't recur elsewhere. > In any case, a comment would really be good to avoid future mistakes. Good point, I'll add something. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
