3.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Larry Finger <[email protected]> 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 <[email protected]> Tested-by: yury <[email protected]> Signed-off-by: Larry Finger <[email protected]> Signed-off-by: John W. Linville <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/net/wireless/b43/main.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -2413,6 +2413,7 @@ 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) { @@ -2459,6 +2460,10 @@ start_ieee80211: if (err) goto err_one_core_detach; b43_leds_register(wl->current_dev); + + /* Register HW RNG driver */ + b43_rng_init(wl); + goto out; err_one_core_detach: @@ -4583,9 +4588,6 @@ static void b43_wireless_core_exit(struc 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. */ @@ -4728,9 +4730,6 @@ static int b43_wireless_core_init(struct b43_set_status(dev, B43_STAT_INITIALIZED); - /* Register HW RNG driver */ - b43_rng_init(dev->wl); - out: return err; @@ -5388,6 +5387,9 @@ static void b43_bcma_remove(struct bcma_ b43_one_core_detach(wldev->dev); + /* Unregister HW RNG driver */ + b43_rng_exit(wl); + b43_leds_unregister(wl); ieee80211_free_hw(wl->hw); @@ -5468,6 +5470,9 @@ static void b43_ssb_remove(struct ssb_de 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. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
