On 13/04/17 15:36, David Ahern wrote:
On 4/13/17 6:48 AM, Robert Shearman wrote:
the patches look ok to me, but in testing them I see I refcnt problem.
simple reproducer:
ip li add red type vrf table 254
ip link set dev eth1 vrf red
ip addr add 127.0.0.1/8 dev red
ip link set dev eth1 up
ip li set red up
ping -c1 -w1 -I red 127.0.0.1
ip li del red
--> hangs with 'uregister_netdevice: waiting for red to become free.'
Right, I've reproduced the same and it occurs even without using the
main table and I believe it has been introduced within the last week.
The cached dst on sockets is one known place that causes a hang on a
delete. Basically the delete stalls until the sockets are closed. I have
a patch for sk_rx_dst which is the one I chased down last week.
sk_dst_cache is another possibility.
Neither of those should be at play with the above example because the
ping command runs and then exits.
Thanks for the pointers. My earlier assessment that this was something
recent turned out to be wrong. I've sent a patch against net that fixes
the issue.
Thanks,
Rob
