diff options
| author |   Roland Dreier <rolandd@cisco.com> | 2008-08-19 15:01:32 -0700 |
|---|---|---|
| committer | Roland Dreier <rolandd@cisco.com> | 2008-08-19 15:01:32 -0700 |
| commit | a77a57a1a22afc31891d95879fe3cf2ab03838b0 (patch) | |
| tree | 14f0b4a4e50f4e112d3189c75357e34829d78704 /drivers/infiniband/ulp/ipoib/ipoib_multicast.c | |
| parent | Merge branch 'release-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-acpi-2.6 (diff) | |
| download | linux-dev-a77a57a1a22afc31891d95879fe3cf2ab03838b0.tar.xz linux-dev-a77a57a1a22afc31891d95879fe3cf2ab03838b0.zip | |
IPoIB: Fix deadlock on RTNL in ipoib_stop()
Commit c8c2afe3 ("IPoIB: Use rtnl lock/unlock when changing device
flags") added a call to rtnl_lock() in ipoib_mcast_join_task(), which
is run from the ipoib_workqueue. However, ipoib_stop() (which is run
inside rtnl_lock()) flushes this workqueue, which leads to a deadlock
if the join task is pending.
Fix this by simply not flushing the workqueue from ipoib_stop(). It
turns out that we really don't care about workqueue tasks running
during or after ipoib_stop(), as long as we make sure to flush the
workqueue before unregistering a netdev.
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=1114>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Diffstat (limited to 'drivers/infiniband/ulp/ipoib/ipoib_multicast.c')
| -rw-r--r-- | drivers/infiniband/ulp/ipoib/ipoib_multicast.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c index 8950e9546f4e..ac33c8f3ea85 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c @@ -392,8 +392,16 @@ static int ipoib_mcast_join_complete(int status, &priv->mcast_task, 0); mutex_unlock(&mcast_mutex); - if (mcast == priv->broadcast) + if (mcast == priv->broadcast) { + /* + * Take RTNL lock here to avoid racing with + * ipoib_stop() and turning the carrier back + * on while a device is being removed. + */ + rtnl_lock(); netif_carrier_on(dev); + rtnl_unlock(); + } return 0; } |