Re: [PATCH net-next 1/2] nexthop: Restart nexthop dump based on last dumped nexthop identifier

[Ido Schimmel <idosch@idosch.org>]

On Sun, Apr 18, 2021 at 10:06:41AM -0700, David Ahern wrote:
> On 4/16/21 8:55 AM, Ido Schimmel wrote:
> > From: Ido Schimmel <idosch@nvidia.com>
> > 
> > Currently, a multi-part nexthop dump is restarted based on the number of
> > nexthops that have been dumped so far. This can result in a lot of
> > nexthops not being dumped when nexthops are simultaneously deleted:
> > 
> >  # ip nexthop | wc -l
> >  65536
> >  # ip nexthop flush
> >  Dump was interrupted and may be inconsistent.
> >  Flushed 36040 nexthops
> >  # ip nexthop | wc -l
> >  29496
> > 
> > Instead, restart the dump based on the nexthop identifier (fixed number)
> > of the last successfully dumped nexthop:
> > 
> >  # ip nexthop | wc -l
> >  65536
> >  # ip nexthop flush
> >  Dump was interrupted and may be inconsistent.
> >  Flushed 65536 nexthops
> >  # ip nexthop | wc -l
> >  0
> > 
> > Reported-by: Maksym Yaremchuk <maksymy@nvidia.com>
> > Tested-by: Maksym Yaremchuk <maksymy@nvidia.com>
> > Signed-off-by: Ido Schimmel <idosch@nvidia.com>
> > Reviewed-by: Petr Machata <petrm@nvidia.com>
> > ---
> >  net/ipv4/nexthop.c | 14 ++++++--------
> >  1 file changed, 6 insertions(+), 8 deletions(-)
> > 
> 
> Reviewed-by: David Ahern <dsahern@kernel.org>

Thanks

> 
> Any reason not to put this in -net with a Fixes tag?

I put it in the cover letter:

"Targeting at net-next since this use case never worked, the flow is
pretty obscure and such a large number of nexthops is unlikely to be
used in any real-world scenario."