From: Hans de Goede hdegoede@redhat.com
[ Upstream commit 215792eda008f6a1e7ed9d77fa20d582d22bb114 ]
Commit 041879b12ddb ("drivers: staging: rtl8192bs: Fix deadlock in rtw_joinbss_event_prehandle()") besides fixing the deadlock also modified _rtw_join_timeout_handler() to use spin_[un]lock_irq() instead of spin_[un]lock_bh().
_rtw_join_timeout_handler() calls rtw_do_join() which takes pmlmepriv->scanned_queue.lock using spin_[un]lock_bh(). This spin_unlock_bh() call re-enables softirqs which triggers an oops in kernel/softirq.c: __local_bh_enable_ip() when it calls lockdep_assert_irqs_enabled():
[ 244.506087] WARNING: CPU: 2 PID: 0 at kernel/softirq.c:376 __local_bh_enable_ip+0xa6/0x100 ... [ 244.509022] Call Trace: [ 244.509048] <IRQ> [ 244.509100] _rtw_join_timeout_handler+0x134/0x170 [r8723bs] [ 244.509468] ? __pfx__rtw_join_timeout_handler+0x10/0x10 [r8723bs] [ 244.509772] ? __pfx__rtw_join_timeout_handler+0x10/0x10 [r8723bs] [ 244.510076] call_timer_fn+0x95/0x2a0 [ 244.510200] __run_timers.part.0+0x1da/0x2d0
This oops is causd by the switch to spin_[un]lock_irq() which disables the IRQs for the entire duration of _rtw_join_timeout_handler().
Disabling the IRQs is not necessary since all code taking this lock runs from either user contexts or from softirqs, switch back to spin_[un]lock_bh() to fix this.
Fixes: 041879b12ddb ("drivers: staging: rtl8192bs: Fix deadlock in rtw_joinbss_event_prehandle()") Cc: Duoming Zhou duoming@zju.edu.cn Signed-off-by: Hans de Goede hdegoede@redhat.com Link: https://lore.kernel.org/r/20230221145326.7808-1-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/rtl8723bs/core/rtw_mlme.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme.c b/drivers/staging/rtl8723bs/core/rtw_mlme.c index 26c40042d2bed..f85ef7dd61b24 100644 --- a/drivers/staging/rtl8723bs/core/rtw_mlme.c +++ b/drivers/staging/rtl8723bs/core/rtw_mlme.c @@ -1547,7 +1547,7 @@ void _rtw_join_timeout_handler(struct timer_list *t) if (adapter->bDriverStopped || adapter->bSurpriseRemoved) return;
- spin_lock_irq(&pmlmepriv->lock); + spin_lock_bh(&pmlmepriv->lock);
if (rtw_to_roam(adapter) > 0) { /* join timeout caused by roaming */ while (1) { @@ -1575,7 +1575,7 @@ void _rtw_join_timeout_handler(struct timer_list *t)
}
- spin_unlock_irq(&pmlmepriv->lock); + spin_unlock_bh(&pmlmepriv->lock); }
/*