linux/drivers/infiniband/ulp
Shlomo Pongratz 7e5a90c25f IPoIB: Fix crash due to skb double destruct
After commit b13912bbb4 ("IPoIB: Call skb_dst_drop() once skb is
enqueued for sending"), using connected mode and running multithreaded
iperf for long time, ie

    iperf -c <IP> -P 16 -t 3600

results in a crash.

After the above-mentioned patch, the driver is calling skb_orphan() and
skb_dst_drop() after calling post_send() in ipoib_cm.c::ipoib_cm_send()
(also in ipoib_ib.c::ipoib_send())

The problem with this is, as is written in a comment in both routines,
"it's entirely possible that the completion handler will run before we
execute anything after the post_send()."  This leads to running the
skb cleanup routines simultaneously in two different contexts.

The solution is to always perform the skb_orphan() and skb_dst_drop()
before queueing the send work request.  If an error occurs, then it
will be no different than the regular case where dev_free_skb_any() in
the completion path, which is assumed to be after these two routines.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-02-05 09:35:06 -08:00
..
ipoib IPoIB: Fix crash due to skb double destruct 2013-02-05 09:35:06 -08:00
iser IB/iser: Add more RX CQs to scale out processing of SCSI responses 2012-10-03 21:26:49 -07:00
srp IB/srp: Allow SRP disconnect through sysfs 2012-11-30 17:40:33 -08:00
srpt ib_srpt: Convert TMR path to target_submit_tmr 2012-11-28 11:20:28 -08:00