svn commit: r354149 - head/sys/net

[Renato Botelho]

On 08/11/19 13:27, Renato Botelho wrote:
> On 29/10/19 14:36, Gleb Smirnoff wrote:
>> Author: glebius
>> Date: Tue Oct 29 17:36:06 2019
>> New Revision: 354149
>> URL: https://svnweb.freebsd.org/changeset/base/354149
>>
>> Log:
>>   There is a long standing problem with multicast programming for NICs
>>   and IPv6.  With IPv6 we may call if_addmulti() in context of processing
>>   of an incoming packet.  Usually this is interrupt context.  While most
>>   of the NIC drivers are able to reprogram multicast filters without
>>   sleeping, some of them can't.  An example is e1000 family of drivers.
>>   With iflib conversion the problem was somewhat hidden.  Iflib processes
>>   packets in private taskqueue, so going to sleep doesn't trigger an
>>   assertion.  However, the sleep would block operation of the driver and
>>   following incoming packets would fill the ring and eventually would
>>   start being dropped.  Enabling epoch for the full time of a packet
>>   processing again started to trigger assertions for e1000.
>>   
>>   Fix this problem once and for all using a general taskqueue to call
>>   if_ioctl() method in all cases when if_addmulti() is called in a
>>   non sleeping context.  Note that nobody cares about returned value.
>>   
>>   Reviewed by:	hselasky, kib
>>   Differential Revision:	  https://reviews.freebsd.org/D22154
> 
> Hi Gleb,
> 
> I upgraded my laptop running 13-CURRENT from r354133 to r354437 and it
> crashed during boot as you can see in the pictures [1].  It seems like
> it crashed while it was configuring network.
> 
> After bisect I managed to boot fine with r354148 and reproduce the crash
> with this revision applied.
> 
> Here is the relevant portion of my /etc/rc.conf:
> 
> # Lagg
> ifconfig_em0="up"
> wlans_iwn0="wlan0"
> ifconfig_wlan0="WPA"
> create_args_wlan0="wlanaddr 3c:97:0e:48:3f:f8 up"
> cloned_interfaces="lagg0"
> ifconfig_lagg0="up laggproto failover laggport em0 laggport wlan0 DHCP"
> ifconfig_lagg0_ipv6="inet6 accept_rtadv"
> rtsold_enable="YES"
> 
> [1] https://imgur.com/a/lBtq3FW

I forgot to mention.  If I disable IPv6 on lagg interface the crash is gone.

-- 
Renato Botelho