| Message ID | 20190803133619.10574-2-vladbu@mellanox.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | action fixes for flow_offload infra compatibility | expand |
On 2019/08/03 14:36, Vlad Buslov wrote: > Recently implemented support for police action in flow_offload infra leads > to following rcu usage warning: > > [ 1925.881092] ============================= > [ 1925.881094] WARNING: suspicious RCU usage > [ 1925.881098] 5.3.0-rc1+ #574 Not tainted > [ 1925.881100] ----------------------------- > [ 1925.881104] include/net/tc_act/tc_police.h:57 suspicious rcu_dereference_check() usage! > [ 1925.881106] > other info that might help us debug this: > > [ 1925.881109] > rcu_scheduler_active = 2, debug_locks = 1 > [ 1925.881112] 1 lock held by tc/18591: > [ 1925.881115] #0: 00000000b03cb918 (rtnl_mutex){+.+.}, at: tc_new_tfilter+0x47c/0x970 > [ 1925.881124] > stack backtrace: > [ 1925.881127] CPU: 2 PID: 18591 Comm: tc Not tainted 5.3.0-rc1+ #574 > [ 1925.881130] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 > [ 1925.881132] Call Trace: > [ 1925.881138] dump_stack+0x85/0xc0 > [ 1925.881145] tc_setup_flow_action+0x1771/0x2040 > [ 1925.881155] fl_hw_replace_filter+0x11f/0x2e0 [cls_flower] > [ 1925.881175] fl_change+0xd24/0x1b30 [cls_flower] > [ 1925.881200] tc_new_tfilter+0x3e0/0x970 > [ 1925.881231] ? tc_del_tfilter+0x720/0x720 > [ 1925.881243] rtnetlink_rcv_msg+0x389/0x4b0 > [ 1925.881250] ? netlink_deliver_tap+0x95/0x400 > [ 1925.881257] ? rtnl_dellink+0x2d0/0x2d0 > [ 1925.881264] netlink_rcv_skb+0x49/0x110 > [ 1925.881275] netlink_unicast+0x171/0x200 > [ 1925.881284] netlink_sendmsg+0x224/0x3f0 > [ 1925.881299] sock_sendmsg+0x5e/0x60 > [ 1925.881305] ___sys_sendmsg+0x2ae/0x330 > [ 1925.881309] ? task_work_add+0x43/0x50 > [ 1925.881314] ? fput_many+0x45/0x80 > [ 1925.881329] ? __lock_acquire+0x248/0x1930 > [ 1925.881342] ? find_held_lock+0x2b/0x80 > [ 1925.881347] ? task_work_run+0x7b/0xd0 > [ 1925.881359] __sys_sendmsg+0x59/0xa0 > [ 1925.881375] do_syscall_64+0x5c/0xb0 > [ 1925.881381] entry_SYSCALL_64_after_hwframe+0x49/0xbe > [ 1925.881384] RIP: 0033:0x7feb245047b8 > [ 1925.881388] 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 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 > ec 28 89 54 > [ 1925.881391] RSP: 002b:00007ffc2d2a5788 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > [ 1925.881395] RAX: ffffffffffffffda RBX: 000000005d4497ed RCX: 00007feb245047b8 > [ 1925.881398] RDX: 0000000000000000 RSI: 00007ffc2d2a57f0 RDI: 0000000000000003 > [ 1925.881400] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006 > [ 1925.881403] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000001 > [ 1925.881406] R13: 0000000000480640 R14: 0000000000000012 R15: 0000000000000001 > > Change tcf_police_rate_bytes_ps() and tcf_police_tcfp_burst() helpers to > allow using them from both rtnl and rcu protected contexts. > > Fixes: 8c8cfc6ed274 ("net/sched: add police action to the hardware intermediate representation") > Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Thank you Vlad. Reviewed-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
diff --git a/include/net/tc_act/tc_police.h b/include/net/tc_act/tc_police.h index 8b9ef3664262..cfdc7cb82cad 100644 --- a/include/net/tc_act/tc_police.h +++ b/include/net/tc_act/tc_police.h @@ -54,7 +54,7 @@ static inline u64 tcf_police_rate_bytes_ps(const struct tc_action *act) struct tcf_police *police = to_police(act); struct tcf_police_params *params; - params = rcu_dereference_bh(police->params); + params = rcu_dereference_bh_rtnl(police->params); return params->rate.rate_bytes_ps; } @@ -63,7 +63,7 @@ static inline s64 tcf_police_tcfp_burst(const struct tc_action *act) struct tcf_police *police = to_police(act); struct tcf_police_params *params; - params = rcu_dereference_bh(police->params); + params = rcu_dereference_bh_rtnl(police->params); return params->tcfp_burst; }
Recently implemented support for police action in flow_offload infra leads to following rcu usage warning: [ 1925.881092] ============================= [ 1925.881094] WARNING: suspicious RCU usage [ 1925.881098] 5.3.0-rc1+ #574 Not tainted [ 1925.881100] ----------------------------- [ 1925.881104] include/net/tc_act/tc_police.h:57 suspicious rcu_dereference_check() usage! [ 1925.881106] other info that might help us debug this: [ 1925.881109] rcu_scheduler_active = 2, debug_locks = 1 [ 1925.881112] 1 lock held by tc/18591: [ 1925.881115] #0: 00000000b03cb918 (rtnl_mutex){+.+.}, at: tc_new_tfilter+0x47c/0x970 [ 1925.881124] stack backtrace: [ 1925.881127] CPU: 2 PID: 18591 Comm: tc Not tainted 5.3.0-rc1+ #574 [ 1925.881130] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 1925.881132] Call Trace: [ 1925.881138] dump_stack+0x85/0xc0 [ 1925.881145] tc_setup_flow_action+0x1771/0x2040 [ 1925.881155] fl_hw_replace_filter+0x11f/0x2e0 [cls_flower] [ 1925.881175] fl_change+0xd24/0x1b30 [cls_flower] [ 1925.881200] tc_new_tfilter+0x3e0/0x970 [ 1925.881231] ? tc_del_tfilter+0x720/0x720 [ 1925.881243] rtnetlink_rcv_msg+0x389/0x4b0 [ 1925.881250] ? netlink_deliver_tap+0x95/0x400 [ 1925.881257] ? rtnl_dellink+0x2d0/0x2d0 [ 1925.881264] netlink_rcv_skb+0x49/0x110 [ 1925.881275] netlink_unicast+0x171/0x200 [ 1925.881284] netlink_sendmsg+0x224/0x3f0 [ 1925.881299] sock_sendmsg+0x5e/0x60 [ 1925.881305] ___sys_sendmsg+0x2ae/0x330 [ 1925.881309] ? task_work_add+0x43/0x50 [ 1925.881314] ? fput_many+0x45/0x80 [ 1925.881329] ? __lock_acquire+0x248/0x1930 [ 1925.881342] ? find_held_lock+0x2b/0x80 [ 1925.881347] ? task_work_run+0x7b/0xd0 [ 1925.881359] __sys_sendmsg+0x59/0xa0 [ 1925.881375] do_syscall_64+0x5c/0xb0 [ 1925.881381] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1925.881384] RIP: 0033:0x7feb245047b8 [ 1925.881388] 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 65 8f 0c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 89 54 [ 1925.881391] RSP: 002b:00007ffc2d2a5788 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 1925.881395] RAX: ffffffffffffffda RBX: 000000005d4497ed RCX: 00007feb245047b8 [ 1925.881398] RDX: 0000000000000000 RSI: 00007ffc2d2a57f0 RDI: 0000000000000003 [ 1925.881400] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006 [ 1925.881403] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000001 [ 1925.881406] R13: 0000000000480640 R14: 0000000000000012 R15: 0000000000000001 Change tcf_police_rate_bytes_ps() and tcf_police_tcfp_burst() helpers to allow using them from both rtnl and rcu protected contexts. Fixes: 8c8cfc6ed274 ("net/sched: add police action to the hardware intermediate representation") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> --- include/net/tc_act/tc_police.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)