On Tue, Jul 12, 2016 at 09:37:58PM +0800, Xin Long wrote: > Sometimes we cannot restore route entries, because in kernel > [1] fib_check_nh() > [2] fib_valid_prefsrc() > cause some routes to depend on existence of others while adding. > > For example, we saved all the routes, and flushed all tables > [a] default via 192.168.122.1 dev eth0 > [b] 192.168.122.0/24 dev eth0 src 192.168.122.21 > [c] broadcast 127.0.0.0 dev lo table local src 127.0.0.1 > [d] local 127.0.0.0/8 dev lo table local src 127.0.0.1 > [e] local 127.0.0.1 dev lo table local src 127.0.0.1 > [f] broadcast 127.255.255.255 dev lo table local src 127.0.0.1 > [g] broadcast 192.168.122.0 dev eth0 table local src 192.168.122.21 > [h] local 192.168.122.21 dev eth0 table local src 192.168.122.21 > [i] broadcast 192.168.122.255 dev eth0 table local src 192.168.122.21 > > Now start to restore them: > If we want to add [a], we have to add [b] first, as [1] and > 'via 192.168.122.1' in [a]. > If we want to add [b], we have to add [h] first, as [2] and > 'src 192.168.122.21' in [b]. > > So the correct order to restore should be like: > [e][h] -> [b][c][d][f][g][i] -> [a] > > This patch fixes it by traversing the file 3 times, it only restores > part of them in each run according to the following conditions, to > make sure every entry can be restored successfully. > 1. !gw && (!fib_prefsrc || fib_prefsrc == cfg->fc_dst) > 2. !gw && (fib_prefsrc != cfg->fc_dst) > 3. gw > > Signed-off-by: Xin Long <lucien....@gmail.com>
Acked-by: Phil Sutter <p...@nwl.cc>
