Andy Chou :
> Here are some more results from the MC project. These are 16 errors found
> in 2.4.1 related to inconsistent use of locks. As usual, if you can
> verify any of these or show that they are false positives, please let us
> know by CC'ing [EMAIL PROTECTED]
>
> -Andy Chou
>
> -----------------------------------------------------------------------------
>
> [BUG] error condition
>
>/u2/acc/oses/linux/2.4.1/drivers/net/pcmcia/wavelan_cs.c:2561:wavelan_get_wireless_stats:
> ERROR:LOCK:2528:2561: Inconsistent
> lock using `spin_lock':2528
>
> static iw_stats *
> wavelan_get_wireless_stats(device * dev)
> {
> ...
> --> Lock
> spin_lock_irqsave (&lp->lock, flags);
>
> if(lp == (net_local *) NULL)
> --> Missing unlock?
> return (iw_stats *) NULL;
>
> -----------------------------------------------------------------------------
Thanks for the hint (actually, also thanks to LWN for
reporting this, I don't read the list).
At first, I felt offended to have such an obvious bug in my
driver, and then I check the master copy of the driver in the Pcmcia
package that I maintain, and it doesn't contain this bug. So whoever
did the port from Pcmcia -> kernel introduced this one :-(
Patch attached. Have fun...
Jean
diff -u -p linux/drivers/net/pcmcia/wireless.24d/wavelan_cs.c
linux/drivers/net/pcmcia/wavelan_cs.c
--- linux/drivers/net/pcmcia/wireless.24d/wavelan_cs.c Thu Mar 22 15:08:46 2001
+++ linux/drivers/net/pcmcia/wavelan_cs.c Thu Mar 22 15:10:25 2001
@@ -2524,11 +2524,13 @@ wavelan_get_wireless_stats(device * dev)
printk(KERN_DEBUG "%s: ->wavelan_get_wireless_stats()\n", dev->name);
#endif
+ /* Pure paranoia */
+ if(lp == (net_local *) NULL)
+ return (iw_stats *) NULL;
+
/* Disable interrupts & save flags */
spin_lock_irqsave (&lp->lock, flags);
- if(lp == (net_local *) NULL)
- return (iw_stats *) NULL;
wstats = &lp->wstats;
/* Get data from the mmc */
