Vlad Buslov 67cbf7dedd net: sched: sample: allow accessing psample_group with rtnl ... Recently implemented support for sample action in flow_offload infra leads to following rcu usage warning: [ 1938.234856] ============================= [ 1938.234858] WARNING: suspicious RCU usage [ 1938.234863] 5.3.0-rc1+ #574 Not tainted [ 1938.234866] ----------------------------- [ 1938.234869] include/net/tc_act/tc_sample.h:47 suspicious rcu_dereference_check() usage! [ 1938.234872] other info that might help us debug this: [ 1938.234875] rcu_scheduler_active = 2, debug_locks = 1 [ 1938.234879] 1 lock held by tc/19540: [ 1938.234881] #0: 00000000b03cb918 (rtnl_mutex){+.+.}, at: tc_new_tfilter+0x47c/0x970 [ 1938.234900] stack backtrace: [ 1938.234905] CPU: 2 PID: 19540 Comm: tc Not tainted 5.3.0-rc1+ #574 [ 1938.234908] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017 [ 1938.234911] Call Trace: [ 1938.234922] dump_stack+0x85/0xc0 [ 1938.234930] tc_setup_flow_action+0xed5/0x2040 [ 1938.234944] fl_hw_replace_filter+0x11f/0x2e0 [cls_flower] [ 1938.234965] fl_change+0xd24/0x1b30 [cls_flower] [ 1938.234990] tc_new_tfilter+0x3e0/0x970 [ 1938.235021] ? tc_del_tfilter+0x720/0x720 [ 1938.235028] rtnetlink_rcv_msg+0x389/0x4b0 [ 1938.235038] ? netlink_deliver_tap+0x95/0x400 [ 1938.235044] ? rtnl_dellink+0x2d0/0x2d0 [ 1938.235053] netlink_rcv_skb+0x49/0x110 [ 1938.235063] netlink_unicast+0x171/0x200 [ 1938.235073] netlink_sendmsg+0x224/0x3f0 [ 1938.235091] sock_sendmsg+0x5e/0x60 [ 1938.235097] ___sys_sendmsg+0x2ae/0x330 [ 1938.235111] ? __handle_mm_fault+0x12cd/0x19e0 [ 1938.235125] ? __handle_mm_fault+0x12cd/0x19e0 [ 1938.235138] ? find_held_lock+0x2b/0x80 [ 1938.235147] ? do_user_addr_fault+0x22d/0x490 [ 1938.235160] __sys_sendmsg+0x59/0xa0 [ 1938.235178] do_syscall_64+0x5c/0xb0 [ 1938.235187] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1938.235192] RIP: 0033:0x7ff9a4d597b8 [ 1938.235197] 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 [ 1938.235200] RSP: 002b:00007ffcfe381c48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 1938.235205] RAX: ffffffffffffffda RBX: 000000005d4497f9 RCX: 00007ff9a4d597b8 [ 1938.235208] RDX: 0000000000000000 RSI: 00007ffcfe381cb0 RDI: 0000000000000003 [ 1938.235211] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006 [ 1938.235214] R10: 0000000000404ec2 R11: 0000000000000246 R12: 0000000000000001 [ 1938.235217] R13: 0000000000480640 R14: 0000000000000012 R15: 0000000000000001 Change tcf_sample_psample_group() helper to allow using it from both rtnl and rcu protected contexts. Fixes: a7a7be6087 ("net/sched: add sample action to the hardware intermediate representation") Signed-off-by: Vlad Buslov <vladbu@mellanox.com> Reviewed-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-08-06 14:15:39 -07:00
..
tc_bpf.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
tc_connmark.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tc_csum.h	net: Change TCA_ACT_* to TCA_ID_* to match that of TCA_ID_POLICE	2019-02-10 09:28:43 -08:00
tc_ct.h	net/sched: Introduce action ct	2019-07-09 12:11:59 -07:00
tc_ctinfo.h	net: sched: act_ctinfo: tidy UAPI definition	2019-06-19 17:11:01 -04:00
tc_defact.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tc_gact.h	net/sched: don't dereference a->goto_chain to read the chain index	2019-03-21 13:26:42 -07:00
tc_ife.h	net: tc_act: drop include of module.h from tc_ife.h	2019-04-22 21:50:53 -07:00
tc_ipt.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tc_mirred.h	net: Change TCA_ACT_* to TCA_ID_* to match that of TCA_ID_POLICE	2019-02-10 09:28:43 -08:00
tc_mpls.h	net: sched: add mpls manipulation actions to TC	2019-07-08 19:50:13 -07:00
tc_nat.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
tc_pedit.h	net: Change TCA_ACT_* to TCA_ID_* to match that of TCA_ID_POLICE	2019-02-10 09:28:43 -08:00
tc_police.h	net: sched: police: allow accessing police->params with rtnl	2019-08-06 14:15:39 -07:00
tc_sample.h	net: sched: sample: allow accessing psample_group with rtnl	2019-08-06 14:15:39 -07:00
tc_skbedit.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201	2019-05-30 11:29:52 -07:00
tc_skbmod.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
tc_tunnel_key.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
tc_vlan.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00