From: David Ahern <dsah...@kernel.org>
Date: Fri, 24 May 2019 16:37:07 -0700
> From: David Ahern <dsah...@gmail.com>
>
> I was really surprised that the IPv6 mtu exception followed by redirect
> test was passing as nothing about the code suggests it should. The problem
> is actually with the logic in the test script.
>
> Fix the test cases as follows:
> 1. add debug function to dump the initial and redirect gateway addresses
> for ipv6. This is shown only in verbose mode. It helps verify the
> output of 'route get'.
>
> 2. fix the check_exception logic for the reset case to make sure that
> for IPv4 neither mtu nor redirect appears in the 'route get' output.
> For IPv6, make sure mtu is not present and the gateway is the initial
> R1 lladdr.
>
> 3. fix the reset logic by using a function to delete the routes added by
> initial_route_*. This format works better for the nexthop version of
> the tests.
>
> While improving the test cases, go ahead and ensure that forwarding is
> disabled since IPv6 redirect requires it.
>
> Also, runs with kernel debugging enabled sometimes show a failure with
> one of the ipv4 tests, so spread the pings over longer time interval.
>
> The end result is that 2 tests now show failures:
>
> TEST: IPv6: mtu exception plus redirect [FAIL]
>
> and the VRF version.
>
> This is a bug in the IPv6 logic that will need to be fixed
> separately. Redirect followed by MTU works because __ip6_rt_update_pmtu
> hits the 'if (!rt6_cache_allowed_for_pmtu(rt6))' path and updates the
> mtu on the exception rt6_info.
>
> MTU followed by redirect does not have this logic. rt6_do_redirect
> creates a new exception and then rt6_insert_exception removes the old
> one which has the MTU exception.
>
> Fixes: ec8105352869 ("selftests: Add redirect tests")
> Signed-off-by: David Ahern <dsah...@gmail.com>
Applied, thanks.
