diff options
| author | Mahesh Bandewar <maheshb@google.com> | 2019-07-02 23:16:31 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-07-03 11:24:38 -0700 |
| commit | d62962b37cebdc936e2bfcd69ea685da2c433727 (patch) | |
| tree | 125dc85e5fb0edf767edf12f2e25bf98de66c7eb /drivers/net/loopback.c | |
| parent | dbcdb61aaf1add3fb15f24f7fcbf30c17d5c11db (diff) | |
| download | lwn-d62962b37cebdc936e2bfcd69ea685da2c433727.tar.gz lwn-d62962b37cebdc936e2bfcd69ea685da2c433727.zip | |
loopback: fix lockdep splat
dev_init_scheduler() and dev_activate() expect the caller to
hold RTNL. Since we don't want blackhole device to be initialized
per ns, we are initializing at init.
[ 3.855027] Call Trace:
[ 3.855034] dump_stack+0x67/0x95
[ 3.855037] lockdep_rcu_suspicious+0xd5/0x110
[ 3.855044] dev_init_scheduler+0xe3/0x120
[ 3.855048] ? net_olddevs_init+0x60/0x60
[ 3.855050] blackhole_netdev_init+0x45/0x6e
[ 3.855052] do_one_initcall+0x6c/0x2fa
[ 3.855058] ? rcu_read_lock_sched_held+0x8c/0xa0
[ 3.855066] kernel_init_freeable+0x1e5/0x288
[ 3.855071] ? rest_init+0x260/0x260
[ 3.855074] kernel_init+0xf/0x180
[ 3.855076] ? rest_init+0x260/0x260
[ 3.855078] ret_from_fork+0x24/0x30
Fixes: 4de83b88c66 ("loopback: create blackhole net device similar to loopack.")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/loopback.c')
| -rw-r--r-- | drivers/net/loopback.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 3b39def5471e..14545a8797a8 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -261,8 +261,10 @@ static int __init blackhole_netdev_init(void) if (!blackhole_netdev) return -ENOMEM; + rtnl_lock(); dev_init_scheduler(blackhole_netdev); dev_activate(blackhole_netdev); + rtnl_unlock(); blackhole_netdev->flags |= IFF_UP | IFF_RUNNING; dev_net_set(blackhole_netdev, &init_net); |