[ovs-dev] [ovs-discuss] kernel crash - openvswitch_mod

[Jesse Gross]

On Fri, May 25, 2012 at 3:58 AM, Luiz Ozaki <luiz.ozaki at locaweb.com.br> wrote:
> On 5/16/12 11:47 PM, Jesse Gross wrote:
>>
>> On Wed, May 16, 2012 at 7:45 PM, Ben Pfaff<blp at nicira.com>  wrote:
>>>
>>> I would expect that only a host kernel bug (inside or outside the OVS
>>> kernel module) would cause a host kernel panic and reboot, so I am
>>> surprised at the idea that a bug in Xen tools (in the guest) would cause
>>> a host reboot.  Is that really what you meant?
>>
>> Well, it's also a bug in the host kernel if it allows it but I think I
>> remember a problem along these lines.
>>
> Changed to Dev Mailing...
>
> We might have found the problem in the kernel function "skb_gso_segment"...
> Doing some test to check.
>
> Anyways, looking at the OVS code I see this skb_gso_segment called in other
> places and handled in different ways:
> ./datapath/vport-netdev.c
> ./datapath/tunnel.c
> ./datapath/datapath.c
>
> ./datapath/linux/compat/netdevice.c
>
> Doesn't rpl_skb_gso_segment need to check IS_ERR and return the PTR_ERR if
> it's true ?

No, the caller will perform that check.  rpl_skb_gso_segment() is a
compatibility replacement for skb_gso_segment() on older kernels.  It
needs to return a pointer, not an error code.