kernel/git/stable/linux.git/net/dsa/master.c, branch linux-4.20.y

net: dsa: Fix lockdep false positive splat

2019-02-12T19:02:32+00:00

[ Upstream commit c8101f7729daee251f4f6505f9d135ec08e1342f ] Creating a macvtap on a DSA-backed interface results in the following splat when lockdep is enabled: [ 19.638080] IPv6: ADDRCONF(NETDEV_CHANGE): lan0: link becomes ready [ 23.041198] device lan0 entered promiscuous mode [ 23.043445] device eth0 entered promiscuous mode [ 23.049255] [ 23.049557] ============================================ [ 23.055021] WARNING: possible recursive locking detected [ 23.060490] 5.0.0-rc3-00013-g56c857a1b8d3 #118 Not tainted [ 23.066132] -------------------------------------------- [ 23.071598] ip/2861 is trying to acquire lock: [ 23.076171] 00000000f61990cb (_xmit_ETHER){+...}, at: dev_set_rx_mode+0x1c/0x38 [ 23.083693] [ 23.083693] but task is already holding lock: [ 23.089696] 00000000ecf0c3b4 (_xmit_ETHER){+...}, at: dev_uc_add+0x24/0x70 [ 23.096774] [ 23.096774] other info that might help us debug this: [ 23.103494] Possible unsafe locking scenario: [ 23.103494] [ 23.109584] CPU0 [ 23.112093] ---- [ 23.114601] lock(_xmit_ETHER); [ 23.117917] lock(_xmit_ETHER); [ 23.121233] [ 23.121233] *** DEADLOCK *** [ 23.121233] [ 23.127325] May be due to missing lock nesting notation [ 23.127325] [ 23.134315] 2 locks held by ip/2861: [ 23.137987] #0: 000000003b766c72 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x338/0x4e0 [ 23.146231] #1: 00000000ecf0c3b4 (_xmit_ETHER){+...}, at: dev_uc_add+0x24/0x70 [ 23.153757] [ 23.153757] stack backtrace: [ 23.158243] CPU: 0 PID: 2861 Comm: ip Not tainted 5.0.0-rc3-00013-g56c857a1b8d3 #118 [ 23.166212] Hardware name: Globalscale Marvell ESPRESSOBin Board (DT) [ 23.172843] Call trace: [ 23.175358] dump_backtrace+0x0/0x188 [ 23.179116] show_stack+0x14/0x20 [ 23.182524] dump_stack+0xb4/0xec [ 23.185928] __lock_acquire+0x123c/0x1860 [ 23.190048] lock_acquire+0xc8/0x248 [ 23.193724] _raw_spin_lock_bh+0x40/0x58 [ 23.197755] dev_set_rx_mode+0x1c/0x38 [ 23.201607] dev_set_promiscuity+0x3c/0x50 [ 23.205820] dsa_slave_change_rx_flags+0x5c/0x70 [ 23.210567] __dev_set_promiscuity+0x148/0x1e0 [ 23.215136] __dev_set_rx_mode+0x74/0x98 [ 23.219167] dev_uc_add+0x54/0x70 [ 23.222575] macvlan_open+0x170/0x1d0 [ 23.226336] __dev_open+0xe0/0x160 [ 23.229830] __dev_change_flags+0x16c/0x1b8 [ 23.234132] dev_change_flags+0x20/0x60 [ 23.238074] do_setlink+0x2d0/0xc50 [ 23.241658] __rtnl_newlink+0x5f8/0x6e8 [ 23.245601] rtnl_newlink+0x50/0x78 [ 23.249184] rtnetlink_rcv_msg+0x360/0x4e0 [ 23.253397] netlink_rcv_skb+0xe8/0x130 [ 23.257338] rtnetlink_rcv+0x14/0x20 [ 23.261012] netlink_unicast+0x190/0x210 [ 23.265043] netlink_sendmsg+0x288/0x350 [ 23.269075] sock_sendmsg+0x18/0x30 [ 23.272659] ___sys_sendmsg+0x29c/0x2c8 [ 23.276602] __sys_sendmsg+0x60/0xb8 [ 23.280276] __arm64_sys_sendmsg+0x1c/0x28 [ 23.284488] el0_svc_common+0xd8/0x138 [ 23.288340] el0_svc_handler+0x24/0x80 [ 23.292192] el0_svc+0x8/0xc This looks fairly harmless (no actual deadlock occurs), and is fixed in a similar way to c6894dec8ea9 ("bridge: fix lockdep addr_list_lock false positive splat") by putting the addr_list_lock in its own lockdep class. Signed-off-by: Marc Zyngier Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: dsa: Fix tagging attribute location

2018-12-01T01:17:39+00:00

While introducing the DSA tagging protocol attribute, it was added to the DSA slave network devices, but those actually see untagged traffic (that is their whole purpose). Correct this mistake by putting the tagging sysfs attribute under the DSA master network device where this is the information that we need. While at it, also correct the sysfs documentation mistake that missed the "dsa/" directory component of the attribute. Fixes: 98cdb4807123 ("net: dsa: Expose tagging protocol to user-space") Signed-off-by: Florian Fainelli Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller

net: dsa: Allow providing PHY statistics from CPU port

2018-04-27T15:53:03+00:00

Implement the same type of ethtool diversion that we have for ETH_SS_STATS and make it work with ETH_SS_PHY_STATS. This allows providing PHY level statistics for CPU ports that are directly connecting to a PHY device. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: Pass stringset to ethtool operations

2018-04-27T15:53:03+00:00

Up until now we largely assumed that we were interested in ETH_SS_STATS type of strings for all ethtool operations, this is about to change with the introduction of additional string sets, e.g: ETH_SS_PHY_STATS. Update all functions to take an appropriate stringset argument and act on it when it is different than ETH_SS_STATS for now. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: Do not check for ethtool_ops validity

2018-04-27T15:53:02+00:00

This is completely redundant with what netdev_set_default_ethtool_ops() does, we are always guaranteed to have a valid dev->ethtool_ops pointer, however, within that structure, not all function calls may be populated, so we still have to check them individually. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller

dsa: Pass the port to get_sset_count()

2018-03-04T18:34:18+00:00

By passing the port, we allow different ports to have different statistics. This is useful since some ports have SERDES interfaces with their own statistic counters. Signed-off-by: Andrew Lunn Tested-by: Florian Fainelli Reviewed-by: Vivien Didelot Signed-off-by: David S. Miller

net: dsa: setup and teardown master device

2017-11-09T00:26:49+00:00

Add DSA helpers to setup and teardown a master net device wired to its CPU port. This centralizes the dsa_ptr assignment. This also makes the master ethtool helpers static at the same time. Signed-off-by: Vivien Didelot Signed-off-by: David S. Miller

net: dsa: change dsa_ptr for a dsa_port

2017-10-01T03:15:07+00:00

With DSA, a master net device (CPU facing interface) has a dsa_ptr pointer to which hangs a dsa_switch_tree. This is not correct because a master interface is wired to a dedicated switch port, and because we can theoretically have several master interfaces pointing to several CPU ports of the same switch fabric. Change the master interface's dsa_ptr for the CPU dsa_port pointer. This is a step towards supporting multiple CPU ports. Signed-off-by: Vivien Didelot Signed-off-by: David S. Miller

net: dsa: use cpu_dp in master code

2017-10-01T03:15:07+00:00

Make it clear that the master device is linked to a CPU port by using "cpu_dp" for the dsa_port variable in master.c instead of "port", then use a "port" variable to describe the port index, as usually seen in other places of DSA core. This will make the future patch touching dsa_ptr more readable. There is no functional changes. Signed-off-by: Vivien Didelot Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: move master ethtool code

2017-09-19T23:04:23+00:00

DSA overrides the master device ethtool ops, so that it can inject stats from its dedicated switch CPU port as well. The related code is currently split in dsa.c and slave.c, but it only scopes the master net device. Move it to a new master.c DSA core file. This file will be later extented with master net device specific code. Signed-off-by: Vivien Didelot Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller