On 2013/02/27 15:21, David Miller wrote:

mroute_clean_tables() uses the list after unregister_netdevice_many().

You mean list_for_each_entry_safe(c, next, &mrt->mfc_cache_array[i], list)
in mroute_clean_tables()?

Isn't this list just a member of struct mfc_cache?
I can't find the other codes in mroute_clean_tables uses this list
after unregister_netdevice_many.

Can you please just stop tinkering in this area?  You are making many
careless errors.

Ok,I am fine if you drop this patch,just as commit ceaaec98ad99859ac90ac6863ad0a6cd075d8e0e
said "device is freed without touching its unreg_list". there will be no serious problems
if we don't have this patch.