linux-stable.git/net/core/flow_offload.c, branch v5.4

net: flow_offload: convert block_ing_cb_list to regular list type

2019-08-19T20:02:38+00:00

RCU list block_ing_cb_list is protected by rcu read lock in
flow_block_ing_cmd() and with flow_indr_block_ing_cb_lock mutex in all
functions that use it. However, flow_block_ing_cmd() needs to call blocking
functions while iterating block_ing_cb_list which leads to following
suspicious RCU usage warning:

[  401.510948] =============================
[  401.510952] WARNING: suspicious RCU usage
[  401.510993] 5.3.0-rc3+ #589 Not tainted
[  401.510996] -----------------------------
[  401.511001] include/linux/rcupdate.h:265 Illegal context switch in RCU read-side critical section!
[  401.511004]
               other info that might help us debug this:

[  401.511008]
               rcu_scheduler_active = 2, debug_locks = 1
[  401.511012] 7 locks held by test-ecmp-add-v/7576:
[  401.511015]  #0: 00000000081d71a5 (sb_writers#4){.+.+}, at: vfs_write+0x166/0x1d0
[  401.511037]  #1: 000000002bd338c3 (&of->mutex){+.+.}, at: kernfs_fop_write+0xef/0x1b0
[  401.511051]  #2: 00000000c921c634 (kn->count#317){.+.+}, at: kernfs_fop_write+0xf7/0x1b0
[  401.511062]  #3: 00000000a19cdd56 (&dev->mutex){....}, at: sriov_numvfs_store+0x6b/0x130
[  401.511079]  #4: 000000005425fa52 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x30/0x140
[  401.511092]  #5: 00000000c5822793 (rtnl_mutex){+.+.}, at: unregister_netdevice_notifier+0x35/0x140
[  401.511101]  #6: 00000000c2f3507e (rcu_read_lock){....}, at: flow_block_ing_cmd+0x5/0x130
[  401.511115]
               stack backtrace:
[  401.511121] CPU: 21 PID: 7576 Comm: test-ecmp-add-v Not tainted 5.3.0-rc3+ #589
[  401.511124] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[  401.511127] Call Trace:
[  401.511138]  dump_stack+0x85/0xc0
[  401.511146]  ___might_sleep+0x100/0x180
[  401.511154]  __mutex_lock+0x5b/0x960
[  401.511162]  ? find_held_lock+0x2b/0x80
[  401.511173]  ? __tcf_get_next_chain+0x1d/0xb0
[  401.511179]  ? mark_held_locks+0x49/0x70
[  401.511194]  ? __tcf_get_next_chain+0x1d/0xb0
[  401.511198]  __tcf_get_next_chain+0x1d/0xb0
[  401.511251]  ? uplink_rep_async_event+0x70/0x70 [mlx5_core]
[  401.511261]  tcf_block_playback_offloads+0x39/0x160
[  401.511276]  tcf_block_setup+0x1b0/0x240
[  401.511312]  ? mlx5e_rep_indr_setup_tc_cb+0xca/0x290 [mlx5_core]
[  401.511347]  ? mlx5e_rep_indr_tc_block_unbind+0x50/0x50 [mlx5_core]
[  401.511359]  tc_indr_block_get_and_ing_cmd+0x11b/0x1e0
[  401.511404]  ? mlx5e_rep_indr_tc_block_unbind+0x50/0x50 [mlx5_core]
[  401.511414]  flow_block_ing_cmd+0x7e/0x130
[  401.511453]  ? mlx5e_rep_indr_tc_block_unbind+0x50/0x50 [mlx5_core]
[  401.511462]  __flow_indr_block_cb_unregister+0x7f/0xf0
[  401.511502]  mlx5e_nic_rep_netdevice_event+0x75/0xb0 [mlx5_core]
[  401.511513]  unregister_netdevice_notifier+0xe9/0x140
[  401.511554]  mlx5e_cleanup_rep_tx+0x6f/0xe0 [mlx5_core]
[  401.511597]  mlx5e_detach_netdev+0x4b/0x60 [mlx5_core]
[  401.511637]  mlx5e_vport_rep_unload+0x71/0xc0 [mlx5_core]
[  401.511679]  esw_offloads_disable+0x5b/0x90 [mlx5_core]
[  401.511724]  mlx5_eswitch_disable.cold+0xdf/0x176 [mlx5_core]
[  401.511759]  mlx5_device_disable_sriov+0xab/0xb0 [mlx5_core]
[  401.511794]  mlx5_core_sriov_configure+0xaf/0xd0 [mlx5_core]
[  401.511805]  sriov_numvfs_store+0xf8/0x130
[  401.511817]  kernfs_fop_write+0x122/0x1b0
[  401.511826]  vfs_write+0xdb/0x1d0
[  401.511835]  ksys_write+0x65/0xe0
[  401.511847]  do_syscall_64+0x5c/0xb0
[  401.511857]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  401.511862] RIP: 0033:0x7fad892d30f8
[  401.511868] Code: 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 25 96 0d 00 8b 00 85 c0 75 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 60 c3 0f 1f 80 00 00 00 00 48 83
 ec 28 48 89
[  401.511871] RSP: 002b:00007ffca2a9fad8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  401.511875] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fad892d30f8
[  401.511878] RDX: 0000000000000002 RSI: 000055afeb072a90 RDI: 0000000000000001
[  401.511881] RBP: 000055afeb072a90 R08: 00000000ffffffff R09: 000000000000000a
[  401.511884] R10: 000055afeb058710 R11: 0000000000000246 R12: 0000000000000002
[  401.511887] R13: 00007fad893a8780 R14: 0000000000000002 R15: 00007fad893a3740

To fix the described incorrect RCU usage, convert block_ing_cb_list from
RCU list to regular list and protect it with flow_indr_block_ing_cb_lock
mutex in flow_block_ing_cmd().

Fixes: 1150ab0f1b33 ("flow_offload: support get multi-subsystem block")
Signed-off-by: Vlad Buslov 
Acked-by: Jakub Kicinski 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

flow_offload: support get multi-subsystem block

2019-08-09T01:44:30+00:00

It provide a callback list to find the blocks of tc
and nft subsystems

Signed-off-by: wenxu 
Acked-by: Jakub Kicinski 
Signed-off-by: David S. Miller

flow_offload: move tc indirect block to flow offload

2019-08-09T01:44:30+00:00

move tc indirect block to flow_offload and rename
it to flow indirect block.The nf_tables can use the
indr block architecture.

Signed-off-by: wenxu 
Acked-by: Jakub Kicinski 
Signed-off-by: David S. Miller

net: flow_offload: add flow_block structure and use it

2019-07-20T04:27:45+00:00

This object stores the flow block callbacks that are attached to this
block. Update flow_block_cb_lookup() to take this new object.

This patch restores the block sharing feature.

Fixes: da3eeb904ff4 ("net: flow_offload: add list handling functions")
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: flow_offload: rename tc_setup_cb_t to flow_setup_cb_t

2019-07-20T04:27:45+00:00

Rename this type definition and adapt users.

Signed-off-by: Pablo Neira Ayuso 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: flow_offload: remove netns parameter from flow_block_cb_alloc()

2019-07-20T04:27:45+00:00

No need to annotate the netns on the flow block callback object,
flow_block_cb_is_busy() already checks for used blocks.

Fixes: d63db30c8537 ("net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()")
Signed-off-by: Pablo Neira Ayuso 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

net: flow_offload: add flow_block_cb_is_busy() and use it

2019-07-09T21:38:50+00:00

This patch adds a function to check if flow block callback is already in
use.  Call this new function from flow_block_cb_setup_simple() and from
drivers.

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: David S. Miller

drivers: net: use flow block API

2019-07-09T21:38:50+00:00

This patch updates flow_block_cb_setup_simple() to use the flow block API.
Several drivers are also adjusted to use it.

This patch introduces the per-driver list of flow blocks to account for
blocks that are already in use.

Remove tc_block_offload alias.

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: David S. Miller

net: flow_offload: add flow_block_cb_{priv, incref, decref}()

2019-07-09T21:38:50+00:00

This patch completes the flow block API to introduce:

* flow_block_cb_priv() to access callback private data.
* flow_block_cb_incref() to bump reference counter on this flow block.
* flow_block_cb_decref() to decrement the reference counter.

These functions are taken from the existing tcf_block_cb_priv(),
tcf_block_cb_incref() and tcf_block_cb_decref().

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: David S. Miller

net: flow_offload: add list handling functions

2019-07-09T21:38:50+00:00

This patch adds the list handling functions for the flow block API:

* flow_block_cb_lookup() allows drivers to look up for existing flow blocks.
* flow_block_cb_add() adds a flow block to the per driver list to be registered
  by the core.
* flow_block_cb_remove() to remove a flow block from the list of existing
  flow blocks per driver and to request the core to unregister this.

The flow block API also annotates the netns this flow block belongs to.

Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: David S. Miller