diff options
| author | Larry Finger <Larry.Finger@lwfinger.net> | 2014-01-12 15:11:37 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-06 11:33:57 -0800 |
| commit | dd6ccf171f67ef638f000f6e70bb83c62e6c62c7 (patch) | |
| tree | 9b27aff2fa134adb20556d80c0d005da300badfa | |
| parent | 4aca366c885d29df6ca9803c13fd92e2b4f42854 (diff) | |
b43: Fix lockdep splat
commit 09164043f63c947a49797750a09ca1cd7c31108e upstream.
In https://bugzilla.kernel.org/show_bug.cgi?id=67561, a locking dependency is reported
when b43 is used with hostapd, and rfkill is used to kill the radio output.
The lockdep splat (in part) is as follows:
======================================================
[ INFO: possible circular locking dependency detected ]
3.12.0 #1 Not tainted
-------------------------------------------------------
rfkill/10040 is trying to acquire lock:
(rtnl_mutex){+.+.+.}, at: [<ffffffff8146f282>] rtnl_lock+0x12/0x20
but task is already holding lock:
(rfkill_global_mutex){+.+.+.}, at: [<ffffffffa04832ca>] rfkill_fop_write+0x6a/0x170 [rfkill]
--snip--
Chain exists of:
rtnl_mutex --> misc_mtx --> rfkill_global_mutex
The fix is to move the initialization of the hardware random number generator
outside the code range covered by the rtnl_mutex.
Reported-by: yury <urykhy@gmail.com>
Tested-by: yury <urykhy@gmail.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/wireless/b43/main.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index ccd24f0acb8d..86b2030055d2 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -2424,6 +2424,7 @@ error: static int b43_one_core_attach(struct b43_bus_dev *dev, struct b43_wl *wl); static void b43_one_core_detach(struct b43_bus_dev *dev); +static int b43_rng_init(struct b43_wl *wl); static void b43_request_firmware(struct work_struct *work) { @@ -2475,6 +2476,10 @@ start_ieee80211: goto err_one_core_detach; wl->hw_registred = true; b43_leds_register(wl->current_dev); + + /* Register HW RNG driver */ + b43_rng_init(wl); + goto out; err_one_core_detach: @@ -4636,9 +4641,6 @@ static void b43_wireless_core_exit(struct b43_wldev *dev) if (!dev || b43_status(dev) != B43_STAT_INITIALIZED) return; - /* Unregister HW RNG driver */ - b43_rng_exit(dev->wl); - b43_set_status(dev, B43_STAT_UNINIT); /* Stop the microcode PSM. */ @@ -4795,9 +4797,6 @@ static int b43_wireless_core_init(struct b43_wldev *dev) b43_set_status(dev, B43_STAT_INITIALIZED); - /* Register HW RNG driver */ - b43_rng_init(dev->wl); - out: return err; @@ -5464,6 +5463,9 @@ static void b43_bcma_remove(struct bcma_device *core) b43_one_core_detach(wldev->dev); + /* Unregister HW RNG driver */ + b43_rng_exit(wl); + b43_leds_unregister(wl); ieee80211_free_hw(wl->hw); @@ -5541,6 +5543,9 @@ static void b43_ssb_remove(struct ssb_device *sdev) b43_one_core_detach(dev); + /* Unregister HW RNG driver */ + b43_rng_exit(wl); + if (list_empty(&wl->devlist)) { b43_leds_unregister(wl); /* Last core on the chip unregistered. |