Nikolay Aleksandrov c6894dec8e bridge: fix lockdep addr_list_lock false positive splat ... After promisc mode management was introduced a bridge device could do dev_set_promiscuity from its ndo_change_rx_flags() callback which in turn can be called after the bridge's addr_list_lock has been taken (e.g. by dev_uc_add). This causes a false positive lockdep splat because the port interfaces' addr_list_lock is taken when br_manage_promisc() runs after the bridge's addr list lock was already taken. To remove the false positive introduce a custom bridge addr_list_lock class and set it on bridge init. A simple way to reproduce this is with the following: $ brctl addbr br0 $ ip l add l br0 br0.100 type vlan id 100 $ ip l set br0 up $ ip l set br0.100 up $ echo 1 > /sys/class/net/br0/bridge/vlan_filtering $ brctl addif br0 eth0 Splat: [ 43.684325] ============================================= [ 43.684485] [ INFO: possible recursive locking detected ] [ 43.684636] 4.4.0-rc8+ #54 Not tainted [ 43.684755] --------------------------------------------- [ 43.684906] brctl/1187 is trying to acquire lock: [ 43.685047] (_xmit_ETHER){+.....}, at: [<ffffffff8150169e>] dev_set_rx_mode+0x1e/0x40 [ 43.685460] but task is already holding lock: [ 43.685618] (_xmit_ETHER){+.....}, at: [<ffffffff815072a7>] dev_uc_add+0x27/0x80 [ 43.686015] other info that might help us debug this: [ 43.686316] Possible unsafe locking scenario: [ 43.686743] CPU0 [ 43.686967] ---- [ 43.687197] lock(_xmit_ETHER); [ 43.687544] lock(_xmit_ETHER); [ 43.687886] *** DEADLOCK *** [ 43.688438] May be due to missing lock nesting notation [ 43.688882] 2 locks held by brctl/1187: [ 43.689134] #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff81510317>] rtnl_lock+0x17/0x20 [ 43.689852] #1: (_xmit_ETHER){+.....}, at: [<ffffffff815072a7>] dev_uc_add+0x27/0x80 [ 43.690575] stack backtrace: [ 43.690970] CPU: 0 PID: 1187 Comm: brctl Not tainted 4.4.0-rc8+ #54 [ 43.691270] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 [ 43.691770] ffffffff826a25c0 ffff8800369fb8e0 ffffffff81360ceb ffffffff826a25c0 [ 43.692425] ffff8800369fb9b8 ffffffff810d0466 ffff8800369fb968 ffffffff81537139 [ 43.693071] ffff88003a08c880 0000000000000000 00000000ffffffff 0000000002080020 [ 43.693709] Call Trace: [ 43.693931] [<ffffffff81360ceb>] dump_stack+0x4b/0x70 [ 43.694199] [<ffffffff810d0466>] __lock_acquire+0x1e46/0x1e90 [ 43.694483] [<ffffffff81537139>] ? netlink_broadcast_filtered+0x139/0x3e0 [ 43.694789] [<ffffffff8153b5da>] ? nlmsg_notify+0x5a/0xc0 [ 43.695064] [<ffffffff810d10f5>] lock_acquire+0xe5/0x1f0 [ 43.695340] [<ffffffff8150169e>] ? dev_set_rx_mode+0x1e/0x40 [ 43.695623] [<ffffffff815edea5>] _raw_spin_lock_bh+0x45/0x80 [ 43.695901] [<ffffffff8150169e>] ? dev_set_rx_mode+0x1e/0x40 [ 43.696180] [<ffffffff8150169e>] dev_set_rx_mode+0x1e/0x40 [ 43.696460] [<ffffffff8150189c>] dev_set_promiscuity+0x3c/0x50 [ 43.696750] [<ffffffffa0586845>] br_port_set_promisc+0x25/0x50 [bridge] [ 43.697052] [<ffffffffa05869aa>] br_manage_promisc+0x8a/0xe0 [bridge] [ 43.697348] [<ffffffffa05826ee>] br_dev_change_rx_flags+0x1e/0x20 [bridge] [ 43.697655] [<ffffffff81501532>] __dev_set_promiscuity+0x132/0x1f0 [ 43.697943] [<ffffffff81501672>] __dev_set_rx_mode+0x82/0x90 [ 43.698223] [<ffffffff815072de>] dev_uc_add+0x5e/0x80 [ 43.698498] [<ffffffffa05b3c62>] vlan_device_event+0x542/0x650 [8021q] [ 43.698798] [<ffffffff8109886d>] notifier_call_chain+0x5d/0x80 [ 43.699083] [<ffffffff810988b6>] raw_notifier_call_chain+0x16/0x20 [ 43.699374] [<ffffffff814f456e>] call_netdevice_notifiers_info+0x6e/0x80 [ 43.699678] [<ffffffff814f4596>] call_netdevice_notifiers+0x16/0x20 [ 43.699973] [<ffffffffa05872be>] br_add_if+0x47e/0x4c0 [bridge] [ 43.700259] [<ffffffffa058801e>] add_del_if+0x6e/0x80 [bridge] [ 43.700548] [<ffffffffa0588b5f>] br_dev_ioctl+0xaf/0xc0 [bridge] [ 43.700836] [<ffffffff8151a7ac>] dev_ifsioc+0x30c/0x3c0 [ 43.701106] [<ffffffff8151aac9>] dev_ioctl+0xf9/0x6f0 [ 43.701379] [<ffffffff81254345>] ? mntput_no_expire+0x5/0x450 [ 43.701665] [<ffffffff812543ee>] ? mntput_no_expire+0xae/0x450 [ 43.701947] [<ffffffff814d7b02>] sock_do_ioctl+0x42/0x50 [ 43.702219] [<ffffffff814d8175>] sock_ioctl+0x1e5/0x290 [ 43.702500] [<ffffffff81242d0b>] do_vfs_ioctl+0x2cb/0x5c0 [ 43.702771] [<ffffffff81243079>] SyS_ioctl+0x79/0x90 [ 43.703033] [<ffffffff815eebb6>] entry_SYSCALL_64_fastpath+0x16/0x7a CC: Vlad Yasevich <vyasevic@redhat.com> CC: Stephen Hemminger <stephen@networkplumber.org> CC: Bridge list <bridge@lists.linux-foundation.org> CC: Andy Gospodarek <gospo@cumulusnetworks.com> CC: Roopa Prabhu <roopa@cumulusnetworks.com> Fixes: 2796d0c648 ("bridge: Automatically manage port promiscuous mode.") Reported-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2016-01-15 15:40:45 -05:00
..
netfilter	netfilter: nf_tables: release objects on netns destruction	2015-12-28 18:34:35 +01:00
br_device.c	bridge: fix lockdep addr_list_lock false positive splat	2016-01-15 15:40:45 -05:00
br_fdb.c	switchdev: Pass original device to port netdev driver	2015-12-15 11:58:20 -05:00
br_forward.c	bridge: set is_local and is_static before fdb entry is added to the fdb hashtable	2015-10-30 12:13:05 +09:00
br_if.c	bridge: Propagate vlan add failure to user	2016-01-06 14:42:40 -05:00
br_input.c
br_ioctl.c
br_mdb.c	bridge: Reflect MDB entries to hardware	2016-01-10 16:50:21 -05:00
br_multicast.c
br_netfilter_hooks.c
br_netfilter_ipv6.c
br_netlink.c	netlink: Rightsize IFLA_AF_SPEC size calculation	2015-10-21 19:15:20 -07:00
br_nf_core.c
br_private_stp.h
br_private.h
br_stp_bpdu.c
br_stp_if.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2016-01-06 22:54:18 -05:00
br_stp_timer.c
br_stp.c	switchdev: Pass original device to port netdev driver	2015-12-15 11:58:20 -05:00
br_sysfs_br.c	bridge: use kobj_to_dev instead of to_dev	2015-12-23 22:26:48 -05:00
br_sysfs_if.c
br_vlan.c	bridge: add vlan filtering change for new bridged device	2016-01-06 14:42:41 -05:00
br.c
Kconfig
Makefile