On 22.09.2016 15:03, Eric Dumazet wrote: > On Thu, 2016-09-22 at 13:03 +0200, Hannes Frederic Sowa wrote: >> Signed-off-by: Hannes Frederic Sowa <han...@stressinduktion.org> >> --- >> net/core/net_namespace.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c >> index 2c2eb1b629b11d..a2ace299f28355 100644 >> --- a/net/core/net_namespace.c >> +++ b/net/core/net_namespace.c >> @@ -758,9 +758,11 @@ static int __init net_ns_init(void) >> >> register_pernet_subsys(&net_ns_ops); >> >> + rtnl_lock(); >> rtnl_register(PF_UNSPEC, RTM_NEWNSID, rtnl_net_newid, NULL, NULL); >> rtnl_register(PF_UNSPEC, RTM_GETNSID, rtnl_net_getid, rtnl_net_dumpid, >> NULL); >> + rtnl_unlock(); >> >> return 0; >> } > > Hi Hannes > > Why is this needed here, and not in other places ?
I found this during working on the file and actually saw no live issues (belonged to another series which I just split up). I don't think it is a big issue but wanted the writes to the rtnl_msg_handlers array to be strictly serialized. I was working on adding this to other places, too. Maybe better for net-next even? Theoretically we would need to add a memory barriers to make sure we don't publish uninitialized memory into the array if concurrent readers of the array want to find their function pointers. > Hint : A changelog always help reviewers and future bug hunting. I will add that to v2. Thanks, Hannes
