diff options
| author | Larry Finger <Larry.Finger@lwfinger.net> | 2013-02-25 06:09:24 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-03 22:03:33 (GMT) |
| commit | 66c45d44d42012bd9ad5e5154cd7d2b391b1183e (patch) | |
| tree | 91f2a3d6e6f549c652d2e3eb3fbb77be29df612c /drivers/net | |
| parent | e3d7ed9c659eebbf83fc20e8c80bb3c58a24028d (diff) | |
| download | linux-fsl-qoriq-66c45d44d42012bd9ad5e5154cd7d2b391b1183e.tar.xz | |
b43: Fix lockdep splat on module unload
commit 63a02ce1c5c59baa40b99756492e3ec8d6b51483 upstream.
On unload, b43 produces a lockdep warning that can be summarized in the
following way:
======================================================
[ INFO: possible circular locking dependency detected ]
3.8.0-wl+ #117 Not tainted
-------------------------------------------------------
modprobe/5557 is trying to acquire lock:
((&wl->firmware_load)){+.+.+.}, at: [<ffffffff81062160>] flush_work+0x0/0x2a0
but task is already holding lock:
(rtnl_mutex){+.+.+.}, at: [<ffffffff813bd7d2>] rtnl_lock+0x12/0x20
which lock already depends on the new lock.
[ INFO: possible circular locking dependency detected ]
======================================================
The full output is available at http://lkml.indiana.edu/hypermail/linux/kernel/1302.3/00060.html.
To summarize, commit 6b6fa58 added a 'cancel_work_sync(&wl->firmware_load)'
call in the wrong place.
The fix is to move the cancel_work_sync() call to b43_bcma_remove() and
b43_ssb_remove(). Thanks to Johannes Berg and Michael Buesch for help in
diagnosing the log output.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/wireless/b43/main.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index 806e34c..0568273 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -4214,7 +4214,6 @@ redo: mutex_unlock(&wl->mutex); cancel_delayed_work_sync(&dev->periodic_work); cancel_work_sync(&wl->tx_work); - cancel_work_sync(&wl->firmware_load); mutex_lock(&wl->mutex); dev = wl->current_dev; if (!dev || b43_status(dev) < B43_STAT_STARTED) { @@ -5434,6 +5433,7 @@ static void b43_bcma_remove(struct bcma_device *core) /* We must cancel any work here before unregistering from ieee80211, * as the ieee80211 unreg will destroy the workqueue. */ cancel_work_sync(&wldev->restart_work); + cancel_work_sync(&wl->firmware_load); B43_WARN_ON(!wl); if (!wldev->fw.ucode.data) @@ -5510,6 +5510,7 @@ static void b43_ssb_remove(struct ssb_device *sdev) /* We must cancel any work here before unregistering from ieee80211, * as the ieee80211 unreg will destroy the workqueue. */ cancel_work_sync(&wldev->restart_work); + cancel_work_sync(&wl->firmware_load); B43_WARN_ON(!wl); if (!wldev->fw.ucode.data) |