Re: [PATCH] net: ipv6: Truncate single route when it doesn't fit into dump buffer.

From: Jan Moskyto Matejka
Date: Fri May 12 2017 - 17:43:41 EST


On Fri, May 12, 2017 at 11:34:04PM +0200, Jan Moskyto Matejka wrote:
> On Fri, May 12, 2017 at 11:24:47AM -0400, David Miller wrote:
> > From: Jan Moskyto Matejka <mq@xxxxxx>
> > Date: Fri, 12 May 2017 13:15:10 +0200
> >
> > > -int rt6_dump_route(struct rt6_info *rt, void *p_arg);
> > > +int rt6_dump_route(struct rt6_info *rt, void *p_arg, int truncate);
> >
> > Please use "bool" and "true"/"false" for boolean values.
>
> Missed that, sorry. Will remember next time.
>
> > What does ipv4 do in this situation?
> >
> > I'm hesitant to be OK with adding a new nlmsg flag just for this case
> > if we solve this problem differently and using existing mechanisms
> > elsewhere.
>
> IPv4 is broken the same way as IPv6, with the difference that
> 'ip route append' does not append a new multipath nexthop but
> creates a whole new route.
>
> It is probably impossible to create such a big route via iproute2 tool;
> it is needed to open netlink socket by hand and write there the
> attached file. (It is one nlmsg adding one huge multipath route.)

Oops, it's late evening here. Attached now.
MQ

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