Re: Kernel panic on assertion in if_wpi.c

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Fri, Jan 09, 2015 at 10:00:23AM +0000, chris%chriswareham.net@localhost wrote:
> Hi,
> 
> I upgraded my Dell Latitude D420 to -current, and have run into an issue with
> wpi(4) wireless. It appears to be connected to Manuel Bouyer's recent work
> around power management, as the kernel panics at the following assertion:
> 
> kernel diagnostic assertion "mutex_owned(&sc->sc_rsw_mtx)" failed: file
> "/home/source/ab/HEAD/src/sys/dev/if_wpi.c", line 3309
> 
> A backtrace on the kernel dump shows this to be in wpi_getrfkill after it's
> called from wpi_init.

The attached patch should be enough to fix it; can you please test ?

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--

Index: if_wpi.c
===================================================================
RCS file: /cvsroot/src/sys/dev/pci/if_wpi.c,v
retrieving revision 1.70
diff -u -p -u -r1.70 if_wpi.c
--- if_wpi.c	6 Jan 2015 15:39:54 -0000	1.70
+++ if_wpi.c	9 Jan 2015 12:12:53 -0000
@@ -3197,13 +3197,16 @@ wpi_init(struct ifnet *ifp)
 		goto fail1;
 
 	/* Check the status of the radio switch */
+	mutex_enter(&sc->sc_rsw_mtx);
 	if (wpi_getrfkill(sc)) {
+		mutex_exit(&sc->sc_rsw_mtx);
 		aprint_error_dev(sc->sc_dev,
 		    "radio is disabled by hardware switch\n");
 		ifp->if_flags &= ~IFF_UP;
 		error = EBUSY;
 		goto fail1;
 	}
+	mutex_exit(&sc->sc_rsw_mtx);
 
 	/* wait for thermal sensors to calibrate */
 	for (ntries = 0; ntries < 1000; ntries++) {