From e64add27e1b4874f589e550b4e0ca6715070373f Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Tue, 5 Jun 2012 20:39:32 +0200 Subject: [PATCH] b43: do not call ieee80211_unregister_hw if we are not registred this patch fixes kernel Oops on "rmmod b43" if firmware was not loaded: BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 IP: [] drain_workqueue+0x25/0x142 PGD 153ac6067 PUD 153b82067 PMD 0 Oops: 0000 [#1] SMP Signed-off-by: Oleksij Rempel Signed-off-by: John W. Linville --- drivers/net/wireless/b43/b43.h | 4 ++++ drivers/net/wireless/b43/main.c | 19 ++++++++++++------- 2 files changed, 16 insertions(+), 7 deletions(-) diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h index 67c13af..c06b6cb 100644 --- a/drivers/net/wireless/b43/b43.h +++ b/drivers/net/wireless/b43/b43.h @@ -877,6 +877,10 @@ struct b43_wl { * from the mac80211 subsystem. */ u16 mac80211_initially_registered_queues; + /* Set this if we call ieee80211_register_hw() and check if we call + * ieee80211_unregister_hw(). */ + bool hw_registred; + /* We can only have one operating interface (802.11 core) * at a time. General information about this interface follows. */ diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index 5a39b22..acd03a4 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -2437,6 +2437,7 @@ start_ieee80211: err = ieee80211_register_hw(wl->hw); if (err) goto err_one_core_detach; + wl->hw_registred = true; b43_leds_register(wl->current_dev); goto out; @@ -5299,6 +5300,7 @@ static struct b43_wl *b43_wireless_init(struct b43_bus_dev *dev) hw->queues = modparam_qos ? B43_QOS_QUEUE_NUM : 1; wl->mac80211_initially_registered_queues = hw->queues; + wl->hw_registred = false; hw->max_rates = 2; SET_IEEE80211_DEV(hw, dev->dev); if (is_valid_ether_addr(sprom->et1mac)) @@ -5370,12 +5372,15 @@ static void b43_bcma_remove(struct bcma_device *core) * as the ieee80211 unreg will destroy the workqueue. */ cancel_work_sync(&wldev->restart_work); - /* Restore the queues count before unregistering, because firmware detect - * might have modified it. Restoring is important, so the networking - * stack can properly free resources. */ - wl->hw->queues = wl->mac80211_initially_registered_queues; - b43_leds_stop(wldev); - ieee80211_unregister_hw(wl->hw); + B43_WARN_ON(!wl); + if (wl->current_dev == wldev && wl->hw_registred) { + /* Restore the queues count before unregistering, because firmware detect + * might have modified it. Restoring is important, so the networking + * stack can properly free resources. */ + wl->hw->queues = wl->mac80211_initially_registered_queues; + b43_leds_stop(wldev); + ieee80211_unregister_hw(wl->hw); + } b43_one_core_detach(wldev->dev); @@ -5446,7 +5451,7 @@ static void b43_ssb_remove(struct ssb_device *sdev) cancel_work_sync(&wldev->restart_work); B43_WARN_ON(!wl); - if (wl->current_dev == wldev) { + if (wl->current_dev == wldev && wl->hw_registred) { /* Restore the queues count before unregistering, because firmware detect * might have modified it. Restoring is important, so the networking * stack can properly free resources. */ -- 2.7.4