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isdn: pcbit: fix interruptible_sleep_on race

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interruptible_sleep_on is racy and going away. In case of pcbit,
the driver would run into a timeout if the card is initialized
before we start waiting for it. This uses wait_event to fix the
race. In order to do this, the state machine handling for the
timeout case has to get trivially reorganized so we actually know
whether the timeout has occorred or not.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnd Bergmann 2014-02-26 12:01:52 +01:00 committed by David S. Miller
parent c73b1f6a04
commit e5b3fa1547
1 changed files with 3 additions and 3 deletions
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6
drivers/isdn/pcbit/drv.c
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@ -796,6 +796,7 @@ static void set_running_timeout(unsigned long ptr)
#endif
dev = (struct pcbit_dev *) ptr;
dev->l2_state = L2_DOWN;
wake_up_interruptible(&dev->set_running_wq);
}
@ -818,7 +819,8 @@ static int set_protocol_running(struct pcbit_dev *dev)
add_timer(&dev->set_running_timer);
interruptible_sleep_on(&dev->set_running_wq);
wait_event(dev->set_running_wq, dev->l2_state == L2_RUNNING ||
dev->l2_state == L2_DOWN);
del_timer(&dev->set_running_timer);
@ -842,8 +844,6 @@ static int set_protocol_running(struct pcbit_dev *dev)
printk(KERN_DEBUG "pcbit: initialization failed\n");
printk(KERN_DEBUG "pcbit: firmware not loaded\n");
dev->l2_state = L2_DOWN;
#ifdef DEBUG
printk(KERN_DEBUG "Bank3 = %02x\n",
readb(dev->sh_mem + BANK3));