Kexec Reboot Network Issue

[Simon Horman]

[ CCed Michael Chan, Matt Carlson and Netdev ]

On Thu, Jul 15, 2010 at 11:35:43AM -0400, Richard Genthner wrote:
> On 07/15/2010 10:20 AM, Simon Horman wrote:
> >On Thu, Jul 15, 2010 at 07:59:07AM -0400, Richard Genthner wrote:
> >>I'm currently using the following string:
> >>
> >>kexex --type=elf-x86_64 --args-linux -l /boot/vmlinuz-2.6.18-12.el5
> >>--initrid=/boot/initrd-2.6.18-128.el6.img --append="`cat
> >>/proc/cmdline`"
> >>kexec -e
> >>
> >>Some times we can get to the box from any subnet, other times we can
> >>only get to the box from the same subnet only. Our solution to this
> >>is to down the iface and then restart networking. Has anyone else
> >>run into this issue?
> >Hi Richard,
> >
> >could you be more specific about which NIC you are using?
> >And is it at all possible to test a newer kernel version?
> >
> >What I suspect is happening is that the NIC is getting into an unknown
> >state. And what I'm hoping is that is a problem thats already been
> >addressed.
>
> I would try a different kenerl but our cluster fs has us locked to
> this kernel until we finish the upgrade to the new cluster fs
> version. heres ethtool on the iface
> 
> from lshw
> *-network
>                 description: Ethernet interface
>                 product: NetXtreme BCM5721 Gigabit Ethernet PCI Express
>                 vendor: Broadcom Corporation
>                 physical id: 0
>                 bus info: pci at 0000:03:00.0
>                 logical name: eth0
>                 version: 21
>                 serial: 00:25:64:3b:9c:ae
>                 size: 1GB/s
>                 capacity: 1GB/s
>                 width: 64 bits
>                 clock: 33MHz
>                 capabilities: pm vpd msi pciexpress bus_master
> cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt
> 1000bt-fd autonegotiation
>                 configuration: autonegotiation=on broadcast=yes
> driver=tg3 driverversion=3.93 duplex=full firmware=5721-v3.65,
> ASFIPMI v6.25 ip=172.16.1.123 latency=0 link=yes module=tg3
> multicast=yes port=twisted pair speed=1GB/s

Hi Richard,

first, please don't top-post, its not the done thing in these parts.

I had a quick hunt through the git change log and the onl changed that
jumped out was "[TG3]: Fix msi issue with kexec/kdump"[1], but this
seems to have been back-ported to the initrd-2.6.18-128.el5 (I assume
you meant 5 not 6) kernel.

[1] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=ee6a99b539a50b4e9398938a0a6d37f8bf911550

In any case I strongly suspect that the problem is a kernel problem and as
such can't be solved modifying the kernel or at least tg.ko module (which
is probably in the initrd). I suggest logging bug report with Red Hat.