On Sat, Apr 23, 2016 at 10:20:15PM +0200, Joerg Jung wrote:
> On Tue, Apr 19, 2016 at 10:57:38AM +0200, Caspar Schutijser wrote:
> > Hi bugs@,
> >
> > On my laptop, wsconsctl crashes with a floating point exception when it
> > wants to print keyboard.backlight. It divides by 0.
> >
> > Below is a patch that fixes the issue, output from gdb and my dmesg.
>
> Yes this is a known problem. There were some suggestion to fix this not
> in wsconsctl (but instead in acpithinkpad?).
Given this still isn't fixed here is a diff to do just that and
return an error from the ioctl callback when max is 0.
Index: acpithinkpad.c
===================================================================
RCS file: /cvs/src/sys/dev/acpi/acpithinkpad.c,v
retrieving revision 1.51
diff -u -p -r1.51 acpithinkpad.c
--- acpithinkpad.c 10 Jan 2016 16:30:43 -0000 1.51
+++ acpithinkpad.c 29 Apr 2016 13:05:02 -0000
@@ -630,6 +630,9 @@ thinkpad_get_backlight(struct wskbd_back
kbl->min = 0;
kbl->max = (sc->sc_thinklight >> 8) & 0x0f;
+ if (kbl->max == 0)
+ return (-1);
+
kbl->curval = sc->sc_thinklight & 0x0f;
return 0;
}
