On Sat, Dec 30, 2017 at 02:11:33PM +0100, Dominik Brodowski wrote:
> On Fri, Dec 22, 2017 at 08:20:12AM +0100, Dominik Brodowski wrote:
> > Dear all,
> >
> > once the (wifi) link becomes ready, the following warning is emitted on
> > mainline (v4.15-rc4-202-gead68f216110) on my notebook:
>
> ... and it is still present as of v4.15-rc5-149-g5aa90a845892
... and still present in v4.15-rc7:
[ 0.000000] Linux version 4.15.0-rc7+ (brodo@light) (gcc version 7.2.1
20171224 (GCC)) #2 SMP PREEMPT Mon Jan 8 08:58:57 CET 2018
...
[ 19.182497] wlan0: associated
[ 19.323473] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 19.324512] =============================
[ 19.324525] WARNING: suspicious RCU usage
[ 19.324531] 4.15.0-rc7+ #2 Not tainted
[ 19.324535] -----------------------------
[ 19.324541] /home/brodo/local/kernel/git/linux/net/wireless/util.c:778
suspicious rcu_dereference_check() usage!
[ 19.324545]
other info that might help us debug this:
[ 19.324551]
rcu_scheduler_active = 2, debug_locks = 1
[ 19.324556] 4 locks held by wpa_supplicant/777:
[ 19.324561] #0: (cb_lock){++++}, at: [<00000000a93b95ca>]
genl_rcv+0x15/0x40
[ 19.324590] #1: (genl_mutex){+.+.}, at: [<0000000088de9868>]
genl_rcv_msg+0x7a/0x90
[ 19.324614] #2: (rtnl_mutex){+.+.}, at: [<00000000d05b811d>]
nl80211_pre_doit+0xe9/0x190
[ 19.324639] #3: (&wdev->mtx){+.+.}, at: [<0000000015e6766b>]
nl80211_send_iface+0x319/0x8d0
[ 19.324663]
stack backtrace:
[ 19.324670] CPU: 3 PID: 777 Comm: wpa_supplicant Not tainted 4.15.0-rc7+ #2
[ 19.324674] Hardware name: Dell Inc. XPS 13 9343/0TM99H, BIOS A11 12/08/2016
[ 19.324679] Call Trace:
[ 19.324690] dump_stack+0x67/0x95
[ 19.324698] ieee80211_bss_get_ie+0x66/0x70
[ 19.324707] nl80211_send_iface+0x346/0x8d0
[ 19.324726] nl80211_get_interface+0x4b/0xa0
[ 19.324738] genl_family_rcv_msg+0x32e/0x3f0
[ 19.324747] ? preempt_count_sub+0x92/0xd0
[ 19.324780] genl_rcv_msg+0x47/0x90
[ 19.324787] ? genl_family_rcv_msg+0x3f0/0x3f0
[ 19.324796] netlink_rcv_skb+0x8a/0x120
[ 19.324811] genl_rcv+0x24/0x40
[ 19.324818] netlink_unicast+0x174/0x1f0
[ 19.324831] netlink_sendmsg+0x383/0x3d0
[ 19.324851] sock_sendmsg+0x2d/0x40
[ 19.324859] ___sys_sendmsg+0x2a8/0x300
[ 19.324877] ? netlink_sendmsg+0x13a/0x3d0
[ 19.324919] ? __sys_sendmsg+0x67/0xb0
[ 19.324925] __sys_sendmsg+0x67/0xb0
[ 19.324949] entry_SYSCALL_64_fastpath+0x18/0x85
[ 19.324955] RIP: 0033:0x779ea30ac037
[ 19.324960] RSP: 002b:00007ffd9ea8aa28 EFLAGS: 00000246
Anyone?
Thanks,
Dominik
