Sorry for the time gap, I had to deal with family matters. OK, I patched if_lagg.c to drop and re-acquire the lock around the call to init the underlying driver. I've been running this for some weeks now and haven't seen the boot-hang since. Hopefully I have tested long enough.
Someone more familiar with this driver and use of this lock there
should review this patch and comment.
-jr
Index: sys/net/if_lagg.c
===================================================================
--- sys/net/if_lagg.c (revision 307319)
+++ sys/net/if_lagg.c (working copy)
@@ -995,6 +995,21 @@
LAGG_RUNLOCK(sc, &tracker);
break;
+ case SIOCADDMULTI:
+ case SIOCDELMULTI:
+ /*
+ * Drivers like if_re.c cause a LOR on WLOCK, so we must
+ * drop and re-aquire the lock around the call.
+ */
+ if (lp->lp_ioctl == NULL) {
+ error = EINVAL;
+ break;
+ }
+ LAGG_WUNLOCK(sc);
+ error = (*lp->lp_ioctl)(ifp, cmd, data);
+ LAGG_WLOCK(sc);
+ break;
+
case SIOCSIFCAP:
if (lp->lp_ioctl == NULL) {
error = EINVAL;
On Wed, 28 Dec 2016 00:24:09 -0800 Adrian Chadd <adrian.ch...@gmail.com> wrote:
>
> hi,
>
> yes, the LOR is why the boot hang occurs :(
>
>
>
> -a
>
>
> On 27 December 2016 at 14:30, J.R. Oldroyd <f...@opal.com> wrote:
> > Sorry, Adrian, I'm missing the back-story here and I'm not that
> > familiar with the lagg code.
> >
> > Are you saying that this LOR is likely relevant to this boot hang,
> > or are you saying that this is a known problem that's not relevant?
> >
> > Jan Kokemüller posted some lagg patches. I don't know if they are
> > likely applicable to this problem, but I could try those.
> >
> > https://reviews.freebsd.org/D6845
> > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211689#c4
> >
> > The first removes an RLOCK, but not the one referenced in the LOR
> > report. The second is a patch for the ath/iwm panic. If you're
> > unfamiliar with them, I will study up on this code and patches
> > to get up to speed on it.
> >
> > -jr
> >
> >
> > On Fri, 23 Dec 2016 11:41:33 -0800 Adrian Chadd <adrian.ch...@gmail.com>
> > wrote:
> >>
> >> Right, that's the known lock order issue with lagg. :(
> >>
> >>
> >> -adrian
> >>
> >>
> >> On 23 December 2016 at 11:37, J.R. Oldroyd <f...@opal.com> wrote:
> >> > On Fri, 23 Dec 2016 10:17:34 -0800 Adrian Chadd <adrian.ch...@gmail.com>
> >> > wrote:
> >> >>
> >> >> On 20 December 2016 at 08:18, J.R. Oldroyd <f...@opal.com> wrote:
> >> >> > On Thu, 8 Dec 2016 17:19:26 -0500 "J.R. Oldroyd" <f...@opal.com>
> >> >> > wrote:
> >> >> >>
> >> >> >> On Thu, 08 Dec 2016 21:29:32 +0200 "Andriy Voskoboinyk"
> >> >> >> <s3er...@gmail.com> wrote:
> >> >> >> >
> >> >> >> > Thu, 08 Dec 2016 16:57:19 +0200 було написано J.R. Oldroyd
> >> >> >> > <f...@opal.com>:
> >> >> >> >
> >> >> >> > Is there any additional output with
> >> >> >> > wlandebug_wlan0="scan+state+auth+assoc"
> >> >> >> > in /etc/rc.conf ?
> >> >> >> >
> >> >> >>
> >> >> >> I have put that in and rebooted several times, all times OK.
> >> >> >> I will report back again in due course when it next hangs.
> >> >> >>
> >> >> >> -jr
> >> >> >>
> >> >> >
> >> >> > The boot hang occurred again today. I noted the point of the hang and
> >> >> > rebooted; the log from the good boot with annotation of the previous
> >> >> > hang
> >> >> > point is here [1].
> >> >> >
> >> >> > -jr
> >> >> >
> >> >> > [1]
> >> >> > http://opal.com/jr/freebsd/20161220-fbsd11.3-boot_hang_wlan_debug.txt
> >> >> > _______________________________________________
> >> >> > freebsd-wireless@freebsd.org mailing list
> >> >> > https://lists.freebsd.org/mailman/listinfo/freebsd-wireless
> >> >> > To unsubscribe, send any mail to
> >> >> > "freebsd-wireless-unsubscr...@freebsd.org"
> >> >>
> >> >>
> >> >> can you compile with witness and invariants? I'd like to see if its
> >> >> locking related.
> >> >>
> >> >> thanks
> >> >>
> >> >>
> >> >> -adrian
> >> >>
> >> >>
> >> >
> >> > Hmm, maybe:
> >> >
> >> > Dec 23 14:30:34 shibato kernel: wlan0: ieee80211_swscan_add_scan: chan
> >> > 11g min dwell met (2146895553 > 2146895553)
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_mindwell: called
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: loop start;
> >> > scandone=0
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: chan 11g ->
> >> > 7g [active, dwell min 20ms max 200ms]
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan: calling;
> >> > maxdwell=200
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: waiting
> >> > Dec 23 14:30:34 shibato kernel: re0: link state changed to UP
> >> > Dec 23 14:30:34 shibato kernel: lagg0: link state changed to UP
> >> > Dec 23 14:30:34 shibato kernel: lock order reversal:
> >> > Dec 23 14:30:34 shibato kernel: 1st 0xfffff800095d2208 if_lagg rmlock
> >> > (if_lagg rmlock) @ /usr/src/sys/modules/if_lagg/../../net/if_lagg.c:1530
> >> > Dec 23 14:30:34 shibato kernel: 2nd 0xfffffe0000e10218 re0 (network
> >> > driver) @ dev/re/if_re.c:3433
> >> > Dec 23 14:30:34 shibato kernel: stack backtrace:
> >> > Dec 23 14:30:34 shibato kernel: #0 0xffffffff80a98b60 at
> >> > witness_debugger+0x70
> >> > Dec 23 14:30:34 shibato kernel: #1 0xffffffff80a98a54 at
> >> > witness_checkorder+0xe54
> >> > Dec 23 14:30:34 shibato kernel: #2 0xffffffff80a1c794 at
> >> > __mtx_lock_flags+0xa4
> >> > Dec 23 14:30:34 shibato kernel: #3 0xffffffff8078c279 at re_ioctl+0x3a9
> >> > Dec 23 14:30:34 shibato kernel: #4 0xffffffff8222428e at
> >> > lagg_port_ioctl+0xde
> >> > Dec 23 14:30:34 shibato kernel: #5 0xffffffff80b20bbf at
> >> > if_addmulti+0x39f
> >> > Dec 23 14:30:34 shibato kernel: #6 0xffffffff82224708 at
> >> > lagg_ether_cmdmulti+0x158
> >> > Dec 23 14:30:34 shibato kernel: #7 0xffffffff822219dd at lagg_ioctl+0xdd
> >> > Dec 23 14:30:34 shibato kernel: #8 0xffffffff80b20bbf at
> >> > if_addmulti+0x39f
> >> > Dec 23 14:30:34 shibato kernel: #9 0xffffffff80c35a97 at
> >> > in6_mc_join_locked+0x1d7
> >> > Dec 23 14:30:34 shibato kernel: #10 0xffffffff80c35715 at
> >> > in6_joingroup+0x75
> >> > Dec 23 14:30:34 shibato kernel: #11 0xffffffff80c2f9e9 at
> >> > in6_update_ifa+0x1339
> >> > Dec 23 14:30:34 shibato kernel: #12 0xffffffff80c33eb3 at
> >> > in6_ifattach+0x413
> >> > Dec 23 14:30:34 shibato kernel: #13 0xffffffff80b1fd84 at ifioctl+0xfe4
> >> > Dec 23 14:30:34 shibato kernel: #14 0xffffffff80a9d946 at
> >> > kern_ioctl+0x246
> >> > Dec 23 14:30:34 shibato kernel: #15 0xffffffff80a9d691 at sys_ioctl+0x171
> >> > Dec 23 14:30:34 shibato kernel: #16 0xffffffff80e9d40b at
> >> > amd64_syscall+0x2db
> >> > Dec 23 14:30:34 shibato kernel: #17 0xffffffff80e7d8ab at
> >> > Xfast_syscall+0xfb
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: loop start;
> >> > scandone=0
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: chan 7g ->
> >> > 36a [active, dwell min 20ms max 200ms]
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan: calling;
> >> > maxdwell=200
> >> > Dec 23 14:30:34 shibato kernel: wlan0: scan_curchan_task: waiting
> >> >
> >> > This boot then continued normally, no hang.
> >> >
> >> > -jr
> >
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